I assume you are an adult (if you were a minor, your record could be sealed I think). There are also ways to eventually get your record expunged in some states. It all costs time and money of course.

I also learned the hard way (an attempt) not to quit my drugs cold turkey. You are suicidal for a reason--it is actually easier to think about about that then how stupid (sorry---hope this isn't a trigger---I can relate to the feeling) what you did was and the consequences. Read as much as you can about the legal system including the laws you broke, how the court system works, etc. One way to fight suicidal thoughts is to make a plan to tackle your problems--doing that makes you feel less powerless. You can learn from this. I now take my suicidal thoughts more seriously. Please go to the emergency room if you think you are close to acting on the thought. A good thought--maybe your history of mental illness will convince them to be more lenient on you so don't hide it and let them know you are trying to get the help you need. You can get through this one step at a time......