I think scooterbug gave you some excellent advise.

Is it a bipolar thing, I don't know. I am in a long term relationship and I would never cheat and I don't have a wandering eye what so ever. I do experience hypersexuallity in a manic phase but I keep it with my partner. I had a strict upbringing around these issues so I'm not sure that that isn't an influence here.

However I believe bipolar or not there is still such things as honesty, integrity, and self control. But that might only go so far with some who has bipolar that is not undercontrol or medicated. By no means tho does it equate to you taking the blows and excuseing it as a mere symptom. Part of any relationship relies on both partners working hard to maintain a healthy relationship.