How complicated can it get?

I was just kissed, and none-too-gently propositioned by a married man. And here's the funny bit, I'm in love with another woman. Isn't it maddening! Thing is, were it not for the woman in question, and the wedding band on the man's finger, I would consider his proposition both flattering and attractive. Under these circumstances, though, I'm terrified...
Ironically, or perhaps not so ironically, I spent the last three years wondering why every heterosexual relationship I've been in ended really badly. Then I met the most amazing girl in the whole world, fell head-over-heels for her, and decided that my disasterous romantic past must be because I'm gay. Thing is, I'm not entirely comfortable with that lable, because I don't want to completely discount my past relationships. I really have loved the men I was with in the past. On the other hand, bisexual seems like such a cop-out. So I decided to take things as they come, and enjoy this amazing woman who is such a heady, exciting, comforting, satisfying part of my life. And now I have to deal with this. Of course I'll tell her what happened. But I know her. She'll become all protective, and our mutual friendship with the guy (which has been great up to this point) will become increasingly uncomfortable, and, and, and... Perhaps worst of all, she'll wonder about the kiss. No matter what I say, she'll wonder whether I enjoyed it, and whether I am reconsidering my decision to be with her, and whether I'm really gay, or just confused. We've been through it all before. We were both with men before, and finding one another was something of a shock for both of us, because there is such an inculturated stigma surrounding being gay, and as much as taking the decision to go with it is a no brainer when you love your partner this much, there's always the fear that your family will reject you, and the dull ache that develops when it sinks in that you will never be able to have the child of the person you love, and that your life will never be the way you dreamed as a child. those dreams are hard to let go of. I love her so dearly, I would give it all up all over again, but when I see her reading about test-tube babies, and sperm donors, and see the longing she has for a child of her own, and know that I can never give that to her. And when I feel that gripping, seering jealousy when some man pays her the sort of half hearted compliment that just isn't the same coming from another woman, or see the change in her demeanor when the same sort of compliment is paid me, and know what she's feeling; when I see her do a double-take outside a bridal shop, or feel her tense up when it reaches *that moment* in a romantic comedy we're watchin; when I long to touch her, but see the warning in her eyes because of how public the space is; I wonder whether it's really worth it. I wonder whether she thinks it's worth it, or whether our happiness is causing her more sadness that she needs. And I wonder whether some typical male, taking a chance with someone like me, wouldn't still be able to make her happier in the end.