The way I understand it is that if you are poly then you are able, as you have experienced 30, to have romantic feelings for someone and it only make you feel more love for your partner. Sometimes it feels so exciting that you want to share them with your partner. Not necessarily sexually or romantically but in a friendly, loving, community, family way. If you are mono, from what I get from Mono, you are in love with someone, committed to that and when feelings arise for others it means that those same feelings have died out for your partner. There is nothing wrong or different in either. They just are and need to be figured out for all of us.
As far as talking to your wife goes? Its her journey and you will need to respect that. Make it a project of yours to take on together. Research (lots on here!), talk about people you pass in the street in terms of attraction, talk about what you would do with someone else if that turns you on. Whether your partner would want to hear about your experiences or not. Out of these talks boundaries form. The world is your oyster and the rules are for the two of you to make and are unique to the two of you.
I would avoid the woman you are crushing on for now as you need to be strong in your relationship and go at your wifes pace. Chances are, once you get going on talking and experiencing this new way of thinking you will find that your crush lessons or is turned to someone else who may be more available.
You may find your local poly group, join a dating site... So much to do first. Baby steps with your wife first, she deserves time, space, patience and respectful boundaries. This is a process that should be enjoyed, not rushed if you want to stay healthy.
As for your concern about needing more affection? This can be a big benefit in poly. More lovin, more touchin, and more sex. All of which some people need. Don't jump on all that yet though, but plod slowly closer you your goal. You won't get that feel good feeling if you don't take all the steps patiently.
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