Someone help me

That is just very sad and I'm afraid you are in a very difficult situation. Can I ask something? Have you done something to upset him? Because if your guy is avoiding because of somenthing that you did, then might as well just leave him be to think over on what you have done. Maybe he just needs some space. How long had he been avoiding you? If he'd been avoiding you for a long time and for no reason at all then that might lead me to conclude that he is having his eyes on someone new. The best thing to do is let him go. It's just so painful to love a guy who doesn't share the same feelings with you. And you say it yourself, you are tired of running after him. It is not easy to just let your emotions go, it might take some time but it might be the right thing to do in your situation.

Hi , it could be he is not interested in you anymore or you could have done something to offend him , so you should find out at the opportune moment

One really has not much to go on here. Did you do something to push him away? Is he worth getting back? Has he found some other person to conquest?