Real tragic romance.

Backstory: When I was 15 I met my high school sweetheart. We dated for almost a year and a half, counting the short breakup we had in between. When we did actually break up it was because he was so blackout drunk and slept with someone else. About a year later my brother had passed and he came to comfort and support me. In the week before my brothers funeral I had told him that I still loved him and that I never stopped. After the funeral he then told me that he had been engaged since he got out of rehab two months before. That ended our interactions again. Then 2 years later, he called me while going through a divorce with the girl he told me he was engaged to. I said that I would support him as a friend because I wasn't about to be a rebound-ee. That lasted almost 2 months until we became more than friends with benefits but not quite in a relationship again. After the new year in 2018 he called to tell me that he was still in love with his now ex-wife. Another year passes and he texts/calls me. I had such a big panic attack I got blackout drunk the next night so I could tell him what I had been wanting to without feeling like my chest would explode. Now another 2 years later, he follows me on Instagram (which is a really big deal because he is not a social media person at all) the day after my birthday and finally allowing myself to start talking to people again. I know i shouldn't even be asking for advice about him because it's obvious that I should just forget him. The thing is, he feels like the literal other half of my soul. We have very similar views and interests, we never had a serious fight, we could talk about anything and everything and we have had a lot of fun together. It's hard to walk away from someone when it feels like you're walking away from a piece of yourself.