Welcome! It's lovely to meet you here, and I am glad to hear that you are hoping to connect with some more people here to perhaps get some help generally. I am also sad to hear about the PTSD you have lived with for 20 decades - it's a long time to suffer without adequate help.
I personally have not had PTSD, but there are many who have. I find one of the best ways of using these forums is to speak to others on their own posts, and sharing bits of your own story. I imagine there's a lot you've been through which others could also hear and recognise elements from their own experiences. We have a dedicated section here, but there are also other sections on other mental health topics more generally: https://www.beyondblue.org.au/get-support/online-forums/ptsd-trauma
Anyway, I just wanted to pop by and give you a little welcome!