Suppose he is suicidal? This has nothing to do with you. There are many other things contributing to his "suicidal thoughts" and quite frankly you are not responsible for him. I mean, the guy lives in a tent and has taken up space in your home for various reasons. You can not take the weight of his life onto your shoulders. We are only responsible for ourselves, and taking care of ourselves is of the utmost importance. Boundaries, Boundaries, Boundaries. There is nothing wrong with saying "I need and want to have my home back. I do not want a roommate. I need you to leave." You have the strength to make this happen. Congrats on your sober time. Keep stringing those days together.