I feel like im losing control

Hi there, this is a very new thing for me, I've never posted anything to a blog before. But I feel like I need advice, or help, and no one in my life is really doing that for me. I'm not clinically approved depressed but feel as if I am and have been all my life and am having a very hard time right now. Its going to be a long story so I understand if you don't feel like reading it, but if you have spare time and feel like it, I'd appreciate it.

So, to start... I am a 21 year old girl, with only a mother (due to cancer), college student, diabetic, and i am in a relationship. I have everything that I could want, but the past few months I have been having a really hard time. I'm worried its ruining my relationship with the guy that I love and that's the last thing I want. We have had a long history, about two years now of on and off, mainly because of him. To start our relationship off we started seeing each other for a little bit and then he disappeared and ignored me for the entire summer, avoided any calls or texts, just vanished. At the end of summer, we got back together and I moved out to my college not too far after that. Once out there he did the same thing but would avoid calls and texts for a week or two at a time. He eventually ended it (again around summer), and I didn't hear from him until he moved out to the same school (end of summer). Yet again we got back together and this is now to current day (its been 6 months since then). This past 6 months have been SO hard for both of us. We have fought a lot. I felt like a lot of the things he did upset me and it turned into a fight. For awhile it had to be at least once a week, I'm starting to worry that its me. I'm starting to act irrationally and impulsively. If he ignores me I "freak" out and feel like I HAVE to talk to him and either call him a ton or go straight to his house because most of the time he ignores my calls when something bad happens. The reasons that I get sad seem rational most of the time but I also am starting to realize that I am so much more attached or "clingy" than he is. Most of the time we fight he tells me that he acts poorly because he needs more space and I don't know why but space is so hard for me. I hate going a day without seeing him but he could go a couple days without seeing me and its not a problem. I don't want to be this way, I want to give him the space he needs, i want to be happy on my own, i just don't want to be sad. I'm worried I'm depressed. I'm noticing I get sad often, sometimes for no reason and I'm having a hard time being interested in anything or anyone other than my boyfriend. Today, I called him after school hoping to see him and he had to work on school work (which I understand) and on my way home I just started bawling, I just feel sad, a lot and I'm so scared its getting worse and will eventually be completely uncontrollable. Today I feel like there was no reason to cry, or be upset, maybe I'm stressed from school but i feel like it shouldn't make me break down. I've always battled with being sad my whole life, but this past 6 months has been a lot more than usual and its terrifying me. My boyfriend has wanted to break up 2 or 3 times now, but he decided to keep trying.

I'm not sure what I'm looking for but I know that I need something to change.