Why does a guy started avoiding me after I telling him that I'm not interested to date him?

probably because he knows that you will not date him, and that he has moved on to find someone who would like to date him, and be with him.
He just doesn't want to waste time to try to be with someone that has made it clear that she is not interested in him that way.
Men don't want to be your friends. If you want a man's time and attention you will have to reciprocate with sexual access.
Because he wanted to date you… you aren’t interested so now he is avoiding you.. people don’t tend to stick around people who have rejected them.
Opinion
2Opinion
lol... for real?
why on earth would you think he's going to keep coming around?
Because you aren't interested why would he waste his time
Superb Opinion