Whatever else, you're going to need to do something about your mindset. Frankly, if you're managing at the moment to hold down a job, keep a house together (ie pay rent, feed yourself, manage bills to some degree) you're doing better than many people on here. You're able to manage your symptoms enough to function on some level - those same skills will help you cope with treatment.
What are you currently actively doing towards your recovery? Not what have you done that hasn't worked, or what you've thought of that you "know" won't work - what are you physically doing just now?
Rather than refusing medication, you may need to consider it as an option, instead of shutting down in therapy, you need to communicate with your T, look at grounding and breathing exercises in session, do some reading about window of tolerance yours might be very small but there are ways to expand this so you can work for longer. Write things down to give her in session, talk about how hard it is to talk, tell her when you feel you're spaced out, write to her after session about what happened in session - whatever you need to do. Get a couple of workbooks, there's a good one for dissociation that - with work - can help you be more present in challenging situations and some excellent DBT ones that will help with emotional regulation. Work on self care, rest, sleep, eat well, get outside and walk or run or whatever you do, start a journal, read for pleasure - start the discipline of caring for yourself. Do mindfulness, yoga, things that relax and reset the mind and bring you back into your own body. Look here for work processes to try eg the thread on top ten congnitive distortions.
The reality is there's no silver bullet here, it's a combination of things, done consistently over a long period of time that gets results gradually.
No, it's not quick or easy, recovering from PTSD is some of the hardest work I've ever done, but it hasn't taken 25 years... but oh my goodness it's been hard, painful work. But I was in pain anyway. It may be a long time before you feel recovered, you may feel worse before you get better but if you continue as you are, you're going to go under anyway. At least go under fighting.