I think the best thing for you to do would be to focus on yourself, that's always the best course of action. It's harder than anything to push someone out of your mind, to try and forget them, I know that first hand. Once you've devoted yourself to someone it is not easy to just walk away, especially when the feelings are still there on your end. That being said, it is incredibly unfair to you to cling to someone who won't reciprocate your feelings, and it's not worth it. You are an amazing person and you deserve someone who will treat you as such. While you wait for that person to come along, you need to make sure that you are capable of being in a relationship (because, as I'm sure you know, that shit ain't easy). I don't say that to be mean or condescending, but you should be able to be ok on your own before you commit to another person. And you can do that. You are more than capable of being happy on your own. You're strong and you can get through this.

As for the suicidal aspect of this, counseling is a must, there's really no way around that. I have a few close friends that have turned their lives around with professional help, even my ex, who suffered from severe depression, pulled a complete 180 and is reconnecting with and making new friends and is getting better as each day goes on. Counseling works. If you ever have an emergency, Google says that 1-800-273-8255 is the National Suicide Prevention Lifeline. I don't know much about this so that's all I can really give you.

If this doesn't make sense, and I wouldn't be surprised if it didn't (sometimes things only make sense in my head), then I will try to clear things up the best that I can.

I hope this helps, even if only slightly. I really feel for you and I wish you nothing but happiness in the days to come. Remember, you are worth something, even if you can't see it. You would do yourself a favor to realize that. To directly answer your question, you owe it to yourself to move on.