He will do anything to win her back. She spends a great amount of time with my son behind her current boyfriend's back(They go out all the time.). This give my son hope but she won't take him back completely. He won't give up trying and I am worried about what he might do next. I want him to talk to someone, counseling, but he refuses. How can I make him? He is showing the signs of major depression.

Giving advice to a parent about a grown child's unrequited love is fruitless, I believe. He has to suffer through this on his own, and we aren't talking with him here, making it doubly difficult.

If you hear signs of suicidal thought, you can't call the police and an ambulance. That's the law, even if it sometimes doesn't always work out. It has to be overt. If he is able to confide in you, don't be all alarmist about it. Sometimes people want to be able to say 'I'd rather be dead than go through this anymore' and they just want a listener, and you say you are there to listen, and know that lots of people wish they were dead when someone doesn't love them. If he sounds frantic about it and has specific plans to kill himself, tell him your obligation is to try to keep him alive.

One topic that can be gently worked into conversation about being dumped is ANGER - she is being mean by seeing him, playing both sides, knowing how he's suffering with love, etc etc. Say you would be angry if someone did that to you. Eventually he may realize how angry he should be - she's basically a tease at this point. It isn't fair and right to have him as her comfy guy to come back to and the new one too.