FA confusion?

Okay, recently (around a month ago) I broke up with my boyfriend. He stated he "still wanted to be friends" however a few days after the breakup he blocked me on Snapchat, then a few days later I messaged him on TikTok to see if he was okay, he gave me a bad response and said "im gonna need some time for a while" then blocked me there.

A week goes by and he reposts about me, and it kinda stung, so I blocked him on an alt, and then he clocked back and blocked me on all my other alts and Instagram too. For 3 Mondays in a row, hes reposted something demeaning about our relationship, he reposts something then goes back to his normal reposts.

I genuinley dont understand, how can you go from being someones "dream person" to being so harsh and uncaring.