Ok anon, this is going to be quite large, so hang in there with me. I wanted the answers to the previous before I answered many of the issues you raised, so I could have a better understanding of what you are feeling, thinking and the situation itself.
Anon, your feeling guilty because she died instead of you. This is not something you can control. If it is someones time to go, it is there time. People say they cheated death, so they beat when it was their time to go, but in actual fact, if they cheated it, it wasn't their time to die at all. When its your time to die, you die, and their is little anyone can do about it.

Anon, where you qualified at the time of the accident in CPR, or medical knowledge to remove glass from her stomach? Did you know how to save a life? If not, then what exactly could you have done differently? I don't see you could have done much to be honest, except what you did, by holding her in her last moments upon earth. She was with you, the person she loved. Even if you had medical qualifications or experience, you would have had no tools, nothing to treat her with. You would still be in the same situation. I say this, because sometimes people go running off after an event and try to rectify it occuring again, so they are better qualified. It doesn't change a great deal at the end of the day under those circumstances, where she had lost so much blood so quickly.

Can you tell me why exactly you feel guilty?
I beg to differ anon. If you can't show any positive emotions, then you could not show love towards her. Kind off counters that theory, doesn't it? You can show positive emotions, your just not thinking hard enough. It is always easier to identify negative emotions, because they often are the clearer of the two within the brain. Teaching youself how to find positive emotions, actually isn't that difficult. Basically, for every negative thought you have, you find two positives. For example, your girlfriend died (negative), you love her deeply and where with her in her last moments feeling her warmth and love in return (both positives).

When you apply this to yourself, and perform these actions for every negative thought, over time, it then becomes instinctive to immediately find the positives to counter negatives, which helps you from going into depression over anything negative within your life or thoughts.
Anon, don't be alarmed by nightmares, as they are merely what occurs from fear of trauma. You lost your girlfriend in a car accident, so immediately your mind has a fear of cars, driving, the implication of an accident and also most likely will impact your relationships in the future, ie. girlfriend is driving somewhere, you will be wanting to know she is safe the entire time, which could cause you to lose the relationship because she thinks your controlling her, or being over the top on her safety.

As you heal your trauma, and find reason and logic to help your mind calm itself, your nightmares will subside as a result. Nothing you can do directly trying to stop nightmares will work, because your trauma, and the fear of that trauma is what is feeding your nightmares and producing them. Nothing more. Heal the cause, you no longer have the symptom.

Anon, this is nothing more than the human mind simply not knowing what to do or say. It is easier for him to walk away than to help you deal with your problems through support. Basically, your friend just doesn't know what to do or say, how to help, which makes them feel very lost, inadequate and so forth in regards to being your friend. This is what happens at the root level, your friend just doesn't understand it, hence the easy clear option is to walk away.

Totally incorrect facts within your thoughts anon. You will stop having nightmares once you heal your trauma. You will get back into life once you heal your trauma and learn how to manage PTSD effectively. You will never get over it, because that is impossible. You will however learn to come to terms with your trauma, keep things in perspective, look at the emotional level of the trauma, because that is where the issues lay.

You can heal anon, you just have to do some very hard work in order to achieve it, and trust me, it is hard. Just ask anyone here who is healing / has healed a majority of their trauma. You will spend a lot of time down, depressed and so forth, but that is where the brain is most vunerable to relearning, which is why you must go down in order to come back up further during the healing process. Each time you go down, you will come up stronger.

Anon, I don't agree with this at all. I understand Love, as most people do. Love is a perpetual agreeement, in that if you had died, would you want your girlfriend to never be happy with another person again? Would you want her to merely mourn you for the rest of her life? I doubt it... so why would you think she would be any different? Loving again does not mean you have to stop loving your girlfriend. She left you quickly anon, and that was out of your control, but it doesn't mean that continueing to live your life means you have forgotten her, or stopped loving her.

You will love again anon, have faith in yourself. You just need to be kind to yourself for a while, heal your trauma, and then move on into the rest of your life.

Anon, not only do you mourn, you have to heal trauma. Be patient, and it will come if you want to work yourself hard enough to do so. With self work and time, you will heal and continue life, trust me, I have faith in your ability already.

I'm glad you raised this actually anon, because you need to take your own advice here, "It wasnt my fault". Your dad obviously had issues of his own anon if he killed himself, which means you where merely an object for him to release some of his frustrations, instead of getting counselling.

Anon, just be prepared to reopen it actually, because unless you can stick your hand on your heart and tell me that you don't feel any spite, remorse, or have thoughts about that period, then you will need to heal it also. Whilst one trauma is the catalyst to causing PTSD itself, once PTSD is present, to heal effectively you must heal every ounce of trauma within one's life, otherwise PTSD will use it to feed from. You will know this once you heal your more major trauma's, because aspects will come back too you and be on your mind if they have not been dealt with properly.

Anon, you have to get past this. This is exactly what I mean about not wanting to help yourself. Your therapist cannot help you, if you are not willing to help yourself by being honest with them. You must tell them everything, you must not hold back anything, regardless how uncomfortable you feel in regards to talking about it, you must tell them one way or another. Whether you write it down, print out what you have written here and give that to them, they must know in order to know exactly how to help you best.

Your not doing yourself any favours by not giving them the entire picture, let me just say that. Your not doing yourself any favours by not talking about this with your therapist. Self esteem is very much part of rebuilding life after PTSD, and your therapist knows this. Your therapist can help you directly rebuild self esteem first, in order for you to open up more, be more confident within yourself that what you say is just being you... without fear.

These are flashbacks anon. Flashbacks come in many forms, this being one of them.

This is pretty normal actually anon for someone who lost someone they love very much. Part of it is because your refusing to let go of her. You believe if you let go, you have dismissed her, or no longer love her. Far from it. She is in your heart anon, and whilst you love her, she will always be in your heart. Your trauma is keeping you attached though, more than you need to be.

Very normal part of trauma anon, nothing to worry about. This is another of those symptoms that will subside as you heal trauma.

PTSD is a chemical imbalance of our neurological system. Basically, neurons from one side of our brain decide to switch sides into the less active side off our brain, which is the PTSD itself.

I actually didn't expect you too attend anon. Have you visitied her grave yet anon?

So what your saying, is that when your driving, your also reliving what occured? Has another car hit you from the side since the accident anon, even though you see them coming whilst your driving?