I’m worried that my partner’s cold sore is a sign he’s been cheating – should I get checked?

DEAR DEIDRE: I’M worried that my partner’s cold sore is a sign he’s been cheating.

He denies it but I’m not sure if I believe him. How else could he have got it?

I’m 37 and he’s 40. We’ve been together for five years.

A few days ago, a sore appeared on his lip. He says he doesn’t know what it is, or how it got there.

He thinks it’s because he bites his lip, but it looks like a sore to me.

I am now imagining he’s been kissing another woman or, worse, having oral sex.