My life is better than it's ever been. Why do I fight with myself?

I can't believe I can act like such a baby.
I'm embarrassed. I quietly told the man who I love so much to leave me alone when all he was trying to do was comfort me. I told him to go away from me so that he wouldn't see me in such a dark, foul, fucked up state of mind. I wanted to leave, but I couldn't because I have homework to do,AGAIN, which is why I was so pissed in the first place.Why did I push him away?
I grew up around people who were dark clouds; ticking time-bombs at times. It was scary. Unpleasant. And very immature and unnecessary, I thought. I promised I'd never be that person. I never want to bring that unpleasantness into my loving home.
But here I am. And I feel ridiculous. I am sitting in the bedroom with the door shut closing out the one person who makes me feel so loved.