kath - I to am in a situation where my husband was unfaithful. He too has threatened suicide since I filed for divorce. I am currently under going therapy to deal with everything. The best advice I have gotten from my therapist is when someone threatens to hurt themselves the only thing to do is not react and say "It would make me sad if you chose to hurt yourself". I have done this several times. It is a way of saying I care but if you do so then it is your choice. It is a bullying tactic. Don't give in to it.
-------------------- Love like you have never been hurt. Dance like nobody's watching and sing like nobody's listening.