Maybe I'd feel betrayed, shocked and disappointed since I'm a bit sensitive. I see it as a betrayal, that's why I'd certainly break up with him.

Obviously this person does not take your relationship as seriously as you do. Ask him what your relationship means to him. Then I would let him go.

We say "the writing is on the wall" - ie. it's obvious you shouldn't stay with him/her. So find someone better.

i will close my eyes!!

Let him go (without actually letting him know--just disappear for a while and see it off from a distance)--be grateful for your timely discovery. (It may be a built-in phase of testing/learning--meant for you to gain worldly wisdom and more importantly, self-knowledge.) PS Rejection is a form of protection (in other words, if you insist on persisting through with this kind of an relationship--everybody may end up hurting.)