Missing ex boyfriend? :/

I dated my ex boyfriend for about 8 months. I broke up with him once, got back together with him and broke up again October. Shortly after that I quit the job for that reason and other reasons. There was a lot of drama involved because we worked together, and I was still trying to get over the ex before him. On Snapchat it shows “1 year ago today” memories and keep seeing fun memories from that job and with him. I know I should’ve deleted the pictures, I know people tend to only remember the good when you leave a job or relationship but I can’t help but miss him and miss that time. We ran into each other 2 weeks ago and we had a nice talk, a hug and we texted a few days after to catch up it made me miss what we had. Then he said something about when he gets a girl he won’t text me anymore and I became jealous and was a bit harsh to him and feel bad. Some part of me wants to text him to apologize..but I don’t want to cause him anymore pain than I already have...I was in a very bad place the time we were dating. (Was grieving, trying to graduate high school, and getting over ex) He was very patient and I felt guilty that he had to take on all these moods and emotions I was throwing at him. Bur through out the relationship he was trying to get off of coke, was an alcoholic, and didn’t believe in God which were major issues..but he was the sweetest and treated me better than anyone I dated. When we talked that night he said he kept that promise for me and himself to never do that drug again, and seems to be consuming much less alcohol. Which I’m happy that I impacted his life in a positive way...I just miss him and those memories. Should I apologize for being harsh? Or should I just silently wish him the best and not bother him? Is it toxic that I miss someone after breaking up with them?