Are people with bipolar disorder more likely to be unfaithful to their partner because of mania/hypomania?

Have you ever been unfaithful to somebody you truly love while manic?

Has someone ever been unfaithful to you while they were manic?

I have never been unfaithful to anybody, even when tempted. And I honestly never would. It's my number one moral in life and I take it very seriously. My girlfriend was hypomanic (bipolar 2) when she first got to college and developed a drinking/partying problem before I met her, and had 20 one night stands. Obviously this hurts me very much, as it is always something I have seen as sacred. She's such a good loyal person, and she says she would absolutely never cheat on me, and that what we have is what she has always wanted, and she would never waste it especially since she already experienced meaningless hookups. I am afraid that if she becomes hypomanic at any point in our lives (if we last a long time) bad things might happen. I really have a hard time trusting, and her circumstance and diagnosis makes it more difficult. She's on lamactil but I don't think that would prevent any mania.

What are your thoughts on this subject in general or from experience?