What makes a man so clingy and without self-respect?

I’ve met this guy. He loves me but I don’t love him back. I don’t think our relationship is heathy so here what i did to let him go away:
1) i deleted all my twitter accounts and twitter is the only platform we communicate from.
2) i used to put him down, call him stupid because when i talk to him, he drive me so nuts to the extent that i no longer can control my anger. Don’t get me wrong, i am calm and I don’t have anger issues, but that beacuse I don’t match with him at all.
3) i told him that I don’t love you back, there is no future for our relationship , he keeps sending me love messages everyday even though i never reply to one of them.
4) he emailed me saying he thinks match together and our differences even after I explain to him the relationship is not healthy and it makes me angry all the time. It’s not healthy for u either
5) I don’t answer his messages. I read them and ignore them but he keeps updating to me about his day !!!
Note: i am 24 ans he is 35! So he is not a teenager! He should understands that!
I don’t want him but he is so fucking clingy and dumb? Are there any ways that let him go away without hurting him because sometimes i feel quite guilty !
What makes a man so clingy and without self-respect?
Post Opinion