Finish college first, if your attempt isn't successful you'll probably spend a lot more time there than you have to making up classes you missed due to you being in the hospital and it'll probably make you even more suicidal. I can't tell you what to do though, but I'd wait until you have your first post-grad job. I know that you're hurting OP and I get the pain but why go so far in your academics just to get so far? You're in college for a reason.
I agree with this 100%. I can feel your pain, but if you can hang on until you finish college, you'll at least have your degree if your attempt(s) fail, which improve your chances of having a good income and material quality of life until you decide to CTB again.
What I'm about to say might feel really belittling, and I'm so sorry if it is, I just want to offer a different perspective: While it's not a guarantee, things can get a lot better when you leave college. I have several friends who really surprised themselves with how much happier they felt, and how much better their chronic mental health issues became, after they got their first post-grad job, or even when they graduated but hadn't yet found a job. I was painfully suicidal 90% of the time from age 16 to 22 when I graduated, and then was quite happy for many years (until a
completely unexpected and extremely unlucky curveball threw me back here).
I know it's so easy for me to say all that, when you have to live through your pain and suffering. And maybe your suffering isn't linked to college at all and won't get better when you graduate - I obviously can't be the judge of that. I just wanted to share my experiences for what they are worth.