Here's a fun one for everyone...
I had an affair with a married co-worker (Kaysie) in early 2009. Her husband had already cheated several times and counseling wasn't working so I figured I wasn't "ruining" a marriage per se. Anyway, she got separated a couple months later and we've been unofficially together ever since (meaning we're not dating but we are exclusive). Earlier this year, Kaysie became fed up with us not being a legit couple and we took a break.
During that time I met another girl, a neighbor actually, named Tara. We hit it off quickly and then after a few weeks Kaysie suddenly wanted to be involved again. I agreed but left out the fact that I'd met someone else during our time off and also kept Tara in the dark. As always tends to happen, both of them found out what was going on in the end. Regardless, Tara and I had already transitioned to just being friends anyway so she wasn't upset and I told Kaysie that things with Tara were over and done with. So at the end of the day there was about a month of overlap between the two girls.
Fast forward 5 months to today. Kaysie, after seemingly being understanding previously, is suddenly furious that I'm still friends with Tara and says I must break off that friendship entirely or she wants out. I told her I'd be willing to compromise and take steps to make her more comfortable with the friendship (have the two meet, not hang out with Tara alone in the evenings, etc). Kaysie clearly doesn't believe I can just be friends with Tara. On some level I suppose that's valid since, if Tara gave the green-light, I'd be all over her... but Tara does have a boyfriend now. Tara and I already discussed our relationship and we agreed to just being friends months ago.
I understand that the situation is uncomfortable for Kaysie, but my view is that she should respect the friendship and not make ultimatums. I want to find a compromise with her on this, but to demand that I completely ditch Tara, who has become a very good friend of mine, seems unfair. If I did that I would only resent Kaysie for it in the end and that would hurt our relationship. I don't make friends easily and am not anxious to lose one of my closest friends for the sake of another.
Is my position really so outrageous? And whether it is or it isn't, I could really use some advice on what steps to take next...