Yes, you do have the right to be unhappy about what happened. However, he isn't the only one who is causing the pain. You are also hurting yourself by constantly dwelling on a relationship that is over. It's like someone constantly picking at a scab. It hurts and bleeds more when you do that. Stop tormenting yourself. No more trying to visit his FB site, or any other contact sites. Don't be calling or emailing him. Delete all of his contact info (phone #, email acct. #, FB address, etc.) that you have. It's past time to move on. Wallowing in the misery of a past relationship just keeps you from being ready to find someone better.
Now, take some deep breaths, remove the contact info, and go find something to occupy your mind and time.
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If a man does not keep pace with his companions, perhaps it is because he hears a different drummer.
Let him step to the music which he hears, however measured, or far away.--Henry David Thoreau