Depression, eating problems, stress?

Ok so, im 18, a university student. I come from a good family and have been brought up well in lovely homes, I've never had anything happen that is terribly traumatic in my life or anything to cause illnesses like depression. However, for years, i have been a very stressed person. It was always just study work that did it, i always took on a lot of work, i work very hard to get to where i want to be in life and will do what it takes to make sure i have a decent future and am happy with what i have. In hight school aged about 14 i had a kind of 'low' period for a while where things got me down quite badly, im not even sure what caused it to be honest and the way i dealt with it was i started to stop eating properly. I started a lot of exersice and even though i have never been over weight and have always been pretty skinny, it wasnt good enough. I made myself sick once, and my parents heard and asked me about it. I denied it and told myself it was stupid and to stop. I did, and i exercised still but not obsessively. People have always seen me as a positive person, but in fact i hardly see the good side of anything. The fact im always stressed about something makes me feel unhappy and i dont really know the difference anymore. Im so used to being stressed it feels normal. So, college, i started to change my diet. I cut things out, made it very healthy, and started to obsessive exercise everyday again because i felt unhappy with my life. Thats continued to this day, only on the way i cut out more things from my diet. Also in college, i self harmed a few times, which is stupid and did nothing. I confided in friends, and a Bf about feeling low and it was just ignored. It felt horrible, that people couldnt see i was unhappy. I broke up with that boy, because he caused me terrible stress and still does. One thing i think is involved is my mum. I love her to pieces, and shes very unhappy with her life. She would change so much, she never to go do what she wanted to do in life and im so much like her. We both attract bad luck, we cant do anything simply without something having to complicate it in someway. She too exercises and worries about her body a bit. I want her to be happy, but i know she isnt. In a way that reflects on me too, because i know what she feels and why. The feeling of just not belonging, life isnt going anywhere, doing things for it not to be appreciated by anyone. I dont really know what im trying to say, except im always stressed, i find it harder to have fun anymore, i dont have time for myself to do something for me to enjoy, i take this 'depressive state' out on my body and dont eat properly. And i know i do it, and it feels silly and stupid and im not sure whether i am being stupid or if i do need to do something about it. When i look back on that it seems so lame, i have no reason to be depressed but thats how ive felt for a while. Cheers for listening to my rant.