Will reaching out to my ex bring closure? How do I heal a pain that won't go away?

I'll try to condense this story as much as I can; but I am still hurting over the loss of my best friend/first love 10 years later. I, a woman (whose gender identity has fluctuated throughout time), had a crush on my best friend as long as I could remember. She confessed in our senior year of highschool and that summer was one of the happiest times in my life. Once we went to university she went to a different school than me and she broke up with me a few months later after revealing she had cheated on me with a guy. We tried to stay friends, because we meant too much to each other but it was painful. We stopped talking in 2014. Then when I came home from university in 2018 I was helping her stepmom (we still remained close) and she said my ex wanted to reach out, but I burst into tears and said I would like to but it's painful. I don't know if she ever passed my message on, but I do regret not talking to her then then. I left home again for graduate school and now that I'm back at home with my parents and unpacking things, I'm seeing how much of my life in highschool and before involved her and has reopened the wound I healed living on my own.

I found that he has begun transitioning to transmasc and now uses he/they/she pronouns and his partner (the one I was cheated on with) transitioned to female.

I don't feel attraction anymore, since I don't know what person he has become and I don't want to get back together, that's not what this is about. It's just painful having a person so important in shaping who I am and being in my life for major events, to nothing. I want to know if he's doing well and how life has treated him. And it feels odd my family still keeps in contact his family, but I haven't seen him in years. I just have a feeling I'm going to leave my hometown at some point for my career, and the time I have at home again means I could reach out before I move away. But is that wise and will that help me heal?