Do you generally think a diagnosis was a positive thing?

Well here goes, I've never posted on a forum before but am curious to know what people think on this subject ....

I am a 46 year old woman, I guess most people would say functioning quite well in life (decent job, nice partner) but I have a lot of oddities that I have never really put together and it was only really my mum saying "I reckon your grandad was probably autistic" and " you're a lot like him" that made me start thinking .... then some research online and well, there's a lot

- as a kid, didn't like playing with other kids and found being sent to go and play with the other (unknown) children excruciating

- as a kid, obsessive interests, about which I had to know everything. Age 5 it was dinosaurs, age 7 volcanoes. Could have told you the name and location of every active one on the planet

- 2 friends throughout school and not much interest in adding to that, very happy with my own company

- teenage on, feeling like I didn't know how to be a girl properly (still don't). I can copy what others do but my heart is not in it. Always thought it was a gender thing, not being a girly girl, but wonder if it's more than that. My worst nightmare would be having to go on a hen night with 12 giggling girls and try to pretend I knew how to behave. 

- I work in IT, I am a coder and a good one. Due to my choice of work, I have worked with several autistic people. Some of them make more sense to me than the other people. Other people don't seem to get them but I do

- And I will rush through the rest, as I am rambling on ..... pathological fear of using the telephone (can't see the person, how am I supposed to know what is going on, resulting in very disjointed and uncomfortable calls), sensitive to loud noise, terrible problems with face blindness (if I saw my neighbour out of context, there's less than 50% chance I would recognise, and if clothing or hair style has changed, less than that), I struggle in large groups, can't focus when everyone is talking at once, prefer to not be around people much, I am a pattern-spotter, photographic memory for numbers, often told I am tactless and say the wrong thing .... then on the other hand I hold down a demanding job, have a good relationship with my lovely man and have still 2 very dear friends

The more I read the more I think my mum might be on to something, but on the other hand I don't know what having that confirmed (or not!) would achieve. Have any of you felt any benefit from having a diagnosis?

There are things that I struggle with, public transport being a big one. The train causes me an enormous amount of stress (too many people, noises, contact with people I don't know) taht I usually arrive at work freaked out/angry. I have had to get off a plane before it took off, because it all became too much and I completely freaked out.  Part of me wonders if I could explain (to myself and my boss) why that is, at least people would understand. Maybe?

It would be really interesting to hear others views on this. Have you bothered with a diagnosis? And if you did, did it make any difference?

thanks all