Hubby in touch with ex-fling but told me he would back off

Dear Coleen I've been married for 18 months, I'm very happy in my relationship, and I'm excited that we've decided to try for a baby soon.

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My problem is, before we met, my husband had an on/off relationship with a woman he's known since they were at college together more than a decade ago.

From what I can gather, they never dated each other officially or exclusively, it was more a case of hooking up for sex when they were both single.