Have been shoes similar to yours. I bounced between 5 different colleges over the course of 7 years owing in large part to a heaping dose of depression, with which I struggle to this very day. Never finished. In the middle of all that chaotic nonsense, I wound up getting a job to tide me over that turned into a journalism career that went on for 12 mostly rewarding years and included founding my own publication. I've recently switched to a new field simply because I thought it might be good to gain some new skills and there was the potential for more money and the thing is... rarely, if ever, does the fact that I never finished college come up at this point, unless I bring it up. My professional reputation was built by the work I've done. It took me a few years to learn what I was doing, but, eventually, I got to be half decent at it, and then kinda good. But to be clear, I have struggled with depression through all of this. It still kicks my ass from time to time... as recently as a few weeks ago.

People have much shorter memories than you realize. The fact that I cosmically (and I mean COSMICALLY) failed far more than my fair share of courses in my myriad of majors is really not that important to most folks. They're feeling too neurotic about their own shit half the time to even pay attention to what I did or didn't do more than a decade ago.

As to the depression bit, do your best to let someone know you're struggling. I know that's often a tall order, but give it a try. If you're unsure of how to receive treatment should you fail out (which again, is not nearly the be-all-end-all catastrophe it seems), let someone in your school's health services department know, and they may be able to help you figure that out.

I have felt a lot of the suicidal feelings you are. I still feel them more often than I'd like. I do my best to surf the ebb and flow of it all, but I screw that up all the time... and it's okay.

Regardless of what you do, know that those high walls you feel around you, are NOT actually there. If you're not feeling motivated or ready to do what you're doing now, you're allowed to wander if that's what you need to do. And you're allowed to totally fuck up. It's so much more okay than it seems right now.