I would post this in relationships, but I always get told I just need to see a doctor.... which doesn't help the problem. 

So I, (18f), find myself get mad/ upset at my boyfriend (20m) ALOT. It's like I choose to be mad at him. And I feel so guilty, because he is such a nice guy. For an example, just a week or so ago I got mad at my boyfriend for taking me home at the end of the day because he wanted to smoke and he knows I don't like to be around it. Once in the car I immediately sat there with my arms crossed, looking out the window. He then says "You're seriously going to pout even with the sandwich and tea I bought you?" I look down at the food he bought me on my lap and shortly after I started crying and pouting some more. He turned down the radio and felt all bad asking , "baby whats wrong?" and I barely said anything like usual and continued to cry. Then at home I texted him and told him he doesn't love me.

Or just yesterday I showed up to his place not wanting to talk, even though I just got off a trip. We went shopping and I moped around and refused to let him buy me anything. And then I laid down in his bed and decided to be mad at him because he had a bad day the day before and said some things that I didn't like (even though he apologized and we resolved it that day). And he came in and I pouted. He got quite mad at me because he already apologized for having a bad day and I was being stubborn that day.

And finally, when I found out he withdrew from the semester for college I had a total MELTDOWN, and refused to support him even though he simply withdrew for now to get his life together and re evaluate. 

Maybe I already answered my question, but it's just a never ending cycle. I want to just stop acting like a baby, but it is so hard!! But he is definitely a keeper, and I do not want to lose him. Any advice would be appreciated. 