[xDramatick]

Nope.
With my first boyfriend so hell no.
I trust him completely, he's said that he's cheated before [i may add - totally wasn't his fault] and he felt awful afterwards and promised he'd never ever do it again.

I couldn't bring myself to do it either unless I was getting revenge.
I believe in revenge over forgiving+forgetting.
So if he was to cheat on me, I'd probably do it back to him.
Sounds awful but that's me :\

I can say though, I love him, he loves me, and we trust each other completely.
I've been put in various positions by other guys where I've been given the opportunity to cheat, but easily brushed them off. I don't love them. Simple as.