How to tell if it's really depression?

[wayji]

After a short but really bad breakup where I really feel my best friend used me for a few hookups, I became fixated about not being good enough and missing him that I grew anxious every time I had to see him at work. I throw up enough to be considered bulimic on and off but have never been diagnosed.

I've work part time, go to my dream internship twenty hours a week, babysit on the weekends and take five classes, but I still feel depressed and think about him often despite the fact I shouldn't. After the past few months, I realize that I always feel either depressed, anxious, numb or sad. Caffeine doesn't really affect me anymore and even when I get plenty of sleep, I feel exhausted. I can't get excited about doing cool stuff at my internship anymore. I'm trying not to be affected by social media perfectionism or impulse purchases, because shopping and browsing social media for inspiration is a big part of my "image" as the magazine intern where I work.

I don't have health insurance, so I can't really go anywhere for diagnosis but from reading online, I understand I can probably be anything. I've tried to keep myself busy because I thought it would help, and it has, but most of the time I don't have any mindfulness. All those tips about living in the presence just suck and don't work. I've tried keeping planners and diaries and trying to focus but nothing works. I understand that most of the world feels this way, but I don't want to be this way. I am not a positive person, but have always been practical, realistic and fixated on success. I had the resume of a college student when I was only in college because I have always been so on top of my career. I don't want to let down the little girl inside me who worked so hard to be where I am, but nothing I do makes me happy and I know it all stems from what happened with my ex best friend who did everything to push me away from him.

[wayji]

I also wanted to add that I do feel hopeful about finding love someday but I don't want to just go on and date the next guy I see. I don't give gain feelings for someone very easily and I know that I wouldn't be able to handle it right now and I feel very indifferent towards the phrase "move on" when used in relationship talk.