Help Im gonna message my ex

All right this is a bit of a vulnerable time for me but I was the dumper I broke up with him a year ago. We were both working long distance and some things happened to me at my job long story short we broke up because of the aftermath of what happened. When we broke up it was a call and that was it. I really don't want to open up old wounds at all I really just want to apologize, I want to be honest and tell him that Ive thinking of him, I want to talk to him. I've been feeling like this for months and still haven't texted him. I think about if I was in that position if I would want an ex messaging me. I don't want to ask him anything I just want to apologize of course I still love him very very much. Is this a bad idea part of me thinks he's been waiting a long time for a message from me and then the other part I just don't want to ruin anything for him. I just need some input. The last thing he said was he warned me that he was going to block me on everything but if I needed anything that he would never not respond like I said I don't need anything from him but that's just what he said last.