It souds as though you are fairly self-aware in dealing with your jealousy, and believe it is rooted in your lack of anothr companion while she has one. If that is truly it and you don't mind what she has with him as an issue in and of itself, than I see no reason to force yourself to meet the guy if you really don't want to - again, so long as you are correct in your appraisal of the situation. Meeting "the other" is helpful when feeling left out or replaced, as well as just being a good idea in the big picture - but isn't NECESSARY in my humble opinion if there aren't issues there. Wow I'm getting repetative, lol.
As for your stated issue - well, it's flat out true that women in todays society have it easier as far as selecting a mate is concerned. But netween socializing and online dating sites and other options, you can find someone. Perhaps work out a deal with your wife where you get time to socialize and look in return for the tie spent with her boyfriend or something along those lines? And if she enjoyed the mutual girlfriend before and is enjoying this poly relationship with her BF, she certainly should be willing to help set you up with prospects as well!
Talk it over. The more she understands your position, the more you feel understood, the better it all works out in the long run, regardless of who has what going on when.