Open the heart and the self flows through

There seems to many problems with me of late. I seem to be frustrating people more often, though it is always unintentional, but I don't think like them.
I feel that I am unworthy to date for many reasons ad my heart is a bit fragile. One of my guy friends was more than harsh with me for thinking like that but I have my reasons. I got on to him about his attack on another when he can never met him, and seemingly blaming him for my faults.
I just don't think I can honestly make someone happy right now. When i am with someone, i want them to be happy. I want them to be. I failed at that last time.
People get made at me because of my guilt (I feel it but they think i should not). I can not help it. So much pain has happened that, according to some, I fear relationships. I want to disagree, but I fear i see some truth in it...Though i think that those feelings are founded.
I don't fear relationships i fear myself. Relationships are great; relationship with the one you love and deeply care for is one of the best feelings i can wish upon another but when that person leaves this world and you know that maybe you could have done something for them, something to prevent them from taking their life....That hurts deeply. i failed him. i do not want to fail another.
going back to frustrating that one guy for saying i am unworthy, he got frustrated, and after talking with him, i tried hard to figure out what is wrong. i have to be the problem.
i have to. The problem had to me because i can fix me. If the problem wasn't me, if i as not the one who failed, how can i prevent such a thing from happening again? i don't want to go through such a thing again. It hurts so much. At least if i am the one who was not strong enough to help him through it, i could get stronger. If i didn't make him happy enough, i could become happier and make people happy. i just don't know. i can't ask him what i could have done to make him want to keep living, it's to late. He is gone.
if the problem was him...It can't be. It has to be me. I can fix me. I can. Then i can be ready to share my heart again. i will be worthy again to know love...Though i know know it is above me. Should people like me even dare to hope again?