I think these kind of thoughts are very common. They talk about processing a diagnosis almost in a similar way to the "seven stages of grief".
It's a real mixed bag. I'm in the opposite situation where I'm almost certain there is something (ADHD in my case) and I'm now at a place where I want the diagnosis, but probably a year or two ago I was really struggling with - and still do occasionally have moments where I struggle with - the idea that I'm never going to "get better". I'm probably not going to find any magic kind of organisation system which works, DH is going to be forever frustrated with my lack of recall for conversations and instructions, I will often be late, I'm not going to look put together, I can never home educate. Those things are hard often because we've spent years thinking "If I can just.... then I'll finally be able to...." and to realise that it might just be the case that something is actually in the way of that is quite a hard thing. Plus it brings up all of those old things people said to us. "You're just lazy, you do it when you want to." "You're so rude/antisocial sometimes. Why don't my feelings matter to you?" (Oh but they do! So, so much!!) "Why can't you do it like everybody else?" - I spoke earlier in the thread about feeling depressed but feeling as though it "didn't count" as depression because the things I felt down about were true. I am forgetful, disorganised, scruffy, sometimes appear rude, messy, and unmotivated (which always looks like lazy/excuse making). But I can get systems in place which mitigate some of these, and the others I just have to learn to accept. Everybody has flaws.
The positives are that you get to understand some parts of yourself which are good are also related to the ASD, and also as you've found, it gives you firstly permission to stop trying on some things and find ways around them, and secondly a handy way to find (especially online) other people who struggle with the same things, and discuss what works for them and how they handle these issues in a way it would be quite impossible to explain otherwise - because a NT person's way of coping with e.g. an awkward social situation might be quite different to the way a person with ASD might find best to cope with it. The problem might look the same but the underlying reasons will be different and so the solution is different too.