Welcome to the forum! I think you'll get a lot of comments/advice on your post because your situation is a reversal of the situations we see here most often, where one spouse wants to be non-monogamous and the other spouse is miserable in non-monogamy.
You sound like a likeable and thoughtful person, Stevek, and your love and consideration for your wife is wonderful.
I think you and Emma should keep talking about ethical non-monogamy/polyamory/an open marriage without acting on it yet.
You don't need to date Amy in particular just because she's a person who asked you out recently. Amy might not be a good choice if she is okay with a cheating relationship (unethical non-monogamy) because it could mean she won't care about Emma's feelings and your marriage to Emma. If Amy had said she was poly, she might've been a good choice to go on a date with; but either way, there is no need to rush into actually going on dates outside your marriage yet.
But I don't think you should drop the subject either. Emma is offering you a gift that would be the envy of many sexually frustrated people who love their unyieldingly monogamous spouse.
Emma loves you, wants you to be happy, and recognizes that you are giving up a significant part of yourself and your sexual needs by only being with her. She knows you love her and is offering you sexual freedom in case you'd like to no longer have to give up your sexual needs.
It's worth considering whether an ethically non-monogamous marriage is an option that could work for you and Emma, but there are many complications. For example:
- If Emma actually doesn't want to have any sex with you at all anymore, that might be a devastating loss for you, no matter how much sexual freedom with others you have.
- Humans tend to fall in love with people they have good sex with. If you don't want to fall in love with anyone other than Emma, maybe you shouldn't have sex with anyone else. If falling in love with someone else would make you fall out of love with Emma, or would break Emma's heart, it could potentially destroy your marriage.
- Emma might think she'd be fine with it, but might actually not be prepared for how she'd feel if you actually dated someone else.
- What if the person you dated wanted you to leave your wife? What if your wife asked you to stop dating your new partner? Etc.
- You would have to think about what you are actually offering other potential dating partners. Just sex, no emotional attachment? A relationship that is kept secret from your friends and family (except for your wife) and thus is kind of like an affair in many ways? Or would you be open about being poly and willing to face judgment and weirdness in your social circles? If you got a girlfriend, would you introduce her to your friends? To your kids? Etc.
You and Emma should keep communicating about this and learning more about non-monogamy and all its variations. Read this forum, learn about polyamory.
One thing I'm confused about. You wrote:
I didn't mention a lot of stuff that has been suggested here. She did bring up an interesting anecdote. Her colleague is actually in a similar setting. Her colleague's husband is in a similar relationship. Without going into too much details, her colleague's husband has a steady girlfriend for last 7 years. She said that this arrangement works for the three of them.
I told her that I need to think a bit and we moved on to some other topics.
What works for her colleague probably won't work for us. I never had casual sex. So one night stands are off.
I don't understand the above. Who has casual sex in your anecdote? The colleague's husband has had a steady girlfriend for 7 years, so that's not casual sex or one-night stands. Does the colleague herself have one-night stands, while her husband has a steady girlfriend?
If so, that's a good example of what we mean by different types of ethical non-monogamy. The husband here would be practicing polyamory, with a wife and a girlfriend, two separate loving relationships. The colleague (the wife here) would be comfortable with her husband's polyamory but she herself might prefer more casual non-monogamy, so what she wants for herself in her open marriage is one-night stands. Cool, that works for them.
Even if I'm misunderstanding your anecdote, my example might help you think about different shapes that non-monogamous marriages can have.