Am I wrong to walk away?

My best friend has been in love with me for 6 years. I finally decided to give him a chance. Admittedly I fell hard and fast. At first he was giddy with delight. Then immediately become clingy, obcessive and downright annoying. He cried when I complimented a friend for making people smile. He got jealous and possesive when a friend gave me a get well card. The list goes on. He picks fights to get me jealous, then gets angry when it doesn't work [I'm not a jealous person]. Each time he came back apologizing profusely with horrendous excuses of diseases in the family [seriously first his mom, now him]. He's not lying about everything but I'm tired of hurting from this. Everyone says we're mean't to be together but I can't see it anymore. Am I being selfish to walk away and leave us at friends or am I doing the right thing? Why is everyone making me feel guilty about hurting him? And how do I explain my side?