And if she did cheat, who can blame her? Life's not perfect. It's not a perfect thing to do, but it's a realistic risk you take when you enter a relationship with a sought after woman. Or any relationship, really. It's a calculated risk you take.
If you're the kind to try to kill someone because they cheated, you should make that VERY clear to them before they get into any kind of committed relationship with a psycho like you.
To be clear, I'm not talking to YOU, op. I'm just saying in general. Anyone who thinks that beating a cheater is ok should go home and tell their partners that their lives are in danger if they cheat and have that responsible discussion.