Cygnus,

You have gotten great advice on a general level. Let me add a specific mention of bipolar mania. I do not know what kind of mental problems your friend is alluding to, and I am not sure you yourself know, so we do not know the diagnosis of your friend, but ... how would I put it without assuming too much... so let us put it this way: your friend's behavior is not inconsistent with the manic phase of the bipolar illness. People have been known to dump their partners while in mania only to regret it deeply after the manic phase passed. Some were taken back by their partners and for others it was a big lesson and an irrecoverable loss. The way your friend asked you that question sounds extremely impulsive. I almost can picture him flipping a coin to do what the coin says if you do not tell him what to do. So if you are close enough, I would gently tell him that you are concerned because his behavior seems impulsive and is out of character for him (if that is true, indeed).