Same thing happened to me but the fact it happened didnt make you a cuck. I will say I was probably a bit turned on by the fetish prior to me exwife cheating on me. Kicker is I had given her permission if she wanted side action we can but within some rules. I didnt realize by the time I gave her permission she was already doing it. She told me not interested and cheated with at least 2 other men after and left me for 1 and thats when she told me. Not even counting the time she came home at 5am from a girls night and she swears she did nothing.
Needless to say it turned me on when she told me she had been cheating, she thought was weird I wanted sex after. But now I am a sorta cuck with current wife.