@Elna0613,
I haven't but you need to get your head screwed on straight.
Here's the deal:
- You don't have to marry your child's father, ever, to 'do the right thing' - your child will be okay if her parents aren't married to each other. Lots of children are in her position and are just fine. You can coparent effectively without the marriage license.
- Something is missing or off-kilter with your long-term relationship, and that something is you. You never went into that relationship with good intentions if all you were doing was thinking about somebody else every single day (per your post).
- Sounds like your buddy from a decade ago has his own commitment. If he does, then chances are good that he won't drop it for you. Sorry, but the chances of a married man leaving for an affair partner are abysmally small. As in, only 3% leave. See: http://www.nation.co.ke/lifestyle/saturday/Will-he-ever-leave-his-wife-for-you/1216-2688904-ox402nz/index.html
- If he's not married to another (you don't make this clear), then the chances are better but are still not great.
- Affairs give people an adrenaline rush. They aren't the reality of diapers, mortgages, laundry, and dental bills. That, plus their illicit nature, make them irresistible for some people. Step back and recognize how you are being led around by that adrenaline rush.
What to do? Try counseling to figure out what the deal is with you and why you can't commit. Also, talk to your current partner. If you are not all in with marrying him, then please be kind enough to free him up to love someone else. Like I noted above, you can be good parents to your daughter without ever putting a ring on it.
As for this other guy, he might actually mean it when he says he wishes you were both single. Or he might not.
Either way, don't hold your breath.