Nic,
the question you have asked is so key!
How long is a piece of string?..
I don't think one persons' treatment and outcome can be compared to another, really? I guess I have said before that PTSD is all about individual differences; where the trauma stems from, how long the trauma caused PTSD symptoms, the person themself -their strength of mind, charactersitics and personality traits that would correlate with healing, family, and friends, and support systems, etc etc. You get me right? I read somewhere that healing can be dependent on so many other factors. If someone trying to heal has not managed to make many emotional attachments and does not have external support this could hinder their progress. However, as we are all individuals there are no absolutes. Generalisations are given as guidance.
So can you heal in 2-3 months? From the percpetion of a realist I would say that that is a rather tall order. Why?..
CBT as far as I am concerened is one dimension of treatment - I do not beleive that CBT in itself can treat all the symptioms of PTSD. Therefore, to beleive that one method of therapy will alleviate all of your symptoms is rather naieve IMHO.
I can see where you are going with this question, and I know all to well how difficult it is to be on the healing journey, and still manage to function in the world - we all wear many hats and sometimes it gets confusing as to which one you are wearing or whether you can fulfil the role it correlates with.
First off; therapy should start with grounding techniques, these enable you to work through aspects of your trauma bit by bit, and ensure that you can sustain your other life duties. This is fundamental to your success! Applying yourself and actually working through the core issues of your trauma has to be in conjunction with being able to manage the emotions that will arise - I guess you could compare the grounding techniques to a car with wheels that are loose. As soon as you go around to many difficult bends you know exaclty what is going to happen. The wheels will come off and you will end up in a ditch alonside the raod. So my advise is to ask about this before any therapy begins. Remember you are in control of your therapy. You should not feel like a helpless by-stander. Your therapist is a facilitator in your healing journey, they navigate, and you control how fast or slow or when to stop!
Once you have established your grounding work I would suggest that you write any questions you have and take that peice of paper with you, and unitl you are satisfied you understand the answers.
And if you want the honest answer that I have concerning how 2-3 months may affect you? They will be some of the toughset, you know it will be harder before it gets easier. You will no doubt have moments of serenity and have many epiphay's concerning your issues and thses are successes. However, the real marker of success is that you will be coming away from therapy feeling like you have unearthed so muh sh*t that you cannot see straight. You have to dig deep, go right down and pull out all of the stuff that has been corroding your very soul. You have to put a stop to it!
CBT in itself is less invasive IMHO. It really only treats the here and now (some of the symptoms of PTSD. Depends on the model the therapist uses. But generally this is how it is used). So you may be able to use CBT rather like a magnifying lense. It will highlight your reasoning and enable you and your therapist to determine how to start to re-programme yourself (Have a look at cognitive schemas, you may understand this angle better?).
So lovely nic - congratulations on being in therapy. Congratulations on accepting you have things to work on. Congratulations on asking your question - I reckon you knew the real answer? Sometimes we put it out there hoping that people will identify with our question and tell us that 2-3 moths is of course enough

..Your question could be - Is 2-3 months enough for you?
One of my lovely friends on here likes to use dieting as an anlorgy for PTSD. My use of it; there is no miracle diet that will allow you to shed all of the dead weight you have been carrying around. There is only determination, retraining yourself, forming new behaviours and good old fashioned hard work! You can do it! Dig deep and begin!
Sent with love
Spirit x