I’m married but drawn to my ex...

I am a 43-year old married man and have been having strong feelings for an ex-girlfriend I dated a few years before I was married. She and I were supposed to marry, but she moved to another city and we ended up losing touch with each other. I met the woman who would become my wife soon after, and we have been married for almost a decade. We have no children. I think my marriage is okay, but there is nothing special about it. We are not madly in love with each other and it often feels as if I am just sharing a home with this person rather than being married to her in a meaningful way. I don’t know if she feels the same way because we don’t really talk about our feelings, but I get the sense that she wouldn’t care if I was in her life or not. My ex-girlfriend moved back to my city a few weeks ago and reached out. We chatted a few times and I know she is single. I think she still has feelings for me. What should I do?
If your marriage is one of convenience, and neither you nor your wife want to talk about it, that is the problem to address first. Your feelings for your ex can be dealt with later, after you have a better sense of what your married life is like and where it is going. If there is no future, it is better to confront that before you consider acting upon your feelings for someone else, because that is speculative. Why not think about what you want from your marriage and partner, and what she wants for herself. If neither of you confronts those expectations, you won’t be able to get out of the state of limbo you’re in.

Should I tell a friend she is being obnoxious at the risk of losing that friendship?
A friendship where you can’t be honest with someone isn’t really a strong friendship at all.