Why is my ex subbing me when he broke up with me?

Me and my ex were together for 5 months in those 5 months I was openly communicative, he could see me, I was considerate, etc we would only see each other once a week we met each other’s families and all but I found out he was cheating on me the whole time with multiple girls we only communicated the first week of the break up then I broke contact completely for 2 weeks then we got back together on the 3rd week since he showed me after we started talking again that he was going to try by blocking and telling the females in front of me that he wasn’t going to see them anymore he even called one to have me see that all the things he said matched up, we were sharing locations (we did this pre break up) as well as having all his passwords, he saw me more as well. on the second week he was flaking due to family matters but still attentive then on the last week he became distant and broke up with me on a Friday 3 days prior he was “letting his phone die” for 3-4 hours at night which he never did before and his location wouldn’t show and my messages wouldn’t deliver he told me he wasn’t ready for a relationship and had things to do before getting into a serious one and that I deserved better I blocked him on all social media then before I blocked on messages he told me “that’s how we do things now” then I read and blocked him I dont want to see or talk to him he unblocked and refollowed all the girls and even went to a hotel that same night. 5 days later his brother followed me on Insta (he has brothers account) then deleted the request after I left it unanswered then his 12 yr old cousin who lives with them followed me then the next day my friend who’s bffs with his cousin sent me a sub he threw saying that someone who blocks someone due to love will never get over someone but if they move on and don’t block them they truly don’t care. why is he being petty and worried if he broke up with me?
Why is my ex subbing me when he broke up with me?
Post Opinion