I have been there a couple of times so far with relapses, and several times with depression and uncontrollable suicidal feelings, in my year and a bit of recovery. It was scary as hell each time. I don't know what reassurance I can give you except that I have seen steady improvement since my initial injury.

For the immediate issues, do you have the number of a suicide hotline? You might not think you need it, but it's reassuring to have it on hand anyway. I am guessing that you're in the US - here's one that I Googled: 1-800-273-TALK (the URL for the number is http://www.suicidepreventionlifeline.org/).

But I think that the best thing that you can do in the middle term is to focus on creating the right conditions to recover. This means seeing someone to address your depression and suicidal ideation, maybe through student health services. It may also mean adjusting your course load.

Also, the hotline I mentioned may be able refer you to mental health professionals or other resources that could be helpful.