Q. My girlfriend admitted to sleeping with another guy while on a cruise with a group of friends. She says she still loves me and seems genuinely remorseful – should I forgive her?

Ruby says: No – you should not. A partner’s infidelity is only acceptable if you are in the room at the same time, watching from a darkened corner, visible only by the light of your cigarette.

But if she’s been running around on a cruise ship, rutting away with some cabana boy on the poop deck, your judgement must be swift and exacting; you can still salvage your relationship if you want to, but you cannot let her cuckoldry go unpunished. Reparations must be made.

Indeed, if you play your cards right, you could leverage this smutty episode into the relationship being conducted entirely on your terms. Whether it’s getting her do the washing up or take part in a long-harboured sexual fantasy, now is the time to bend her to your will.

Dear Reuben

Reuben says: You know what they say: to err is human, to forgive is divine. People make mistakes – they allow their libidos to run away with them. Crazy shit happens on cruise ships – you’re lucky she only hooked up with one guy.

I met my current girlfriend online, through a dating site called overfiftyandsexy.com. But just as our love began to blossom, I discovered she had met literally dozens of guys through the site and had several of us on rotation.

I was upset initially, but I found it in my heart to forgive her and accept that one man could never be enough for her. We now have a roster – I see her every second weekend and Wednesdays, and the other days are divided between her other boyfriends.

It’s unconventional but just proves there are no rules to govern the human heart.

» Got a sex or relationship worry? Email dearreuben@tntmagazine.com