<human>: My SO and I have been married for six years. I'm f, 32 and he's m, 34. We're pretty open minded on a lot of things and we have a good relationship. My problem is a female friend of his who he is really close to. They hang out a lot and get along really well. I know nothing sexual is going on there but sometimes I worry that it might. Like I said we're pretty open minded and it wouldn't be marriage-ending if they did sleep together but I'd want to know about it first. Sometimes I get tempted to tell him to go ahead and get it over with.
We've talked about his friendship and I'm ok with it because he makes sure I have all the time and affection I need too.
I'm wondering what the best way to approach this might be and hope you can give me some advice, Reddit!

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<bot>: hubby has a close female friend. Think they might want to sleep together; know he won't leave if they do. Advice?