If you have friend or relative who committed suicide, why should you get upset at them? Weren't they upset enough? Try to open to the pain that they had. Try to really open to it. What was the turmoil they had?
If you get upset at them doing it, that is just coming from your own selfishness. You lost something. You didn't want them to do that, you wanted them to stay around. You are only thinking about yourself if you get upset at someone else who committed suicide. So try to open your heart for that person and the mental turmoil and ignorance they obviously had. Now once you do it for that person, open out to the ignorance and mental turmoil of other people around the world who are committing suicide.
You know it is classic, Japan, university exams, end of the year, half a dozen, a dozen, men or women kill themselves because they failed the exams. Just fear of failure. This is incredibly crazy from most of the societies we come from.
Years ago when Clinton was first elected, one of his childhood friends from kindergarten, who Clinton had worked with and always helped him as governor in Arkansas, apparently did something illegal like moving a million dollars in his business the wrong way. He was going to go to jail for some years. Instead, He killed himself. Crazy. But it was just about money. Try to think of them rather than yourself, so that you let go of your anger and open up with compassion for them and their fear.
Now where do they go? What is the Kamma? This is an interesting little point which I am not going to be able to answer it absolutely properly, but basically what they are doing at the end of their life is killing somebody which is negative Kamma. So chances are that killing somebody means you get a negative rebirth. Now depending on how much good Kamma they had maybe that bad rebirth will only be for a short period of time. We don't know.