Minor dilemma

I love Simes and E-J's parties, would be really nice to see them properly, and to catch up with other people who are likely to be there. But me being there would probably make Karen uncomfortable, and perhaps unhappy. I don't want to do that, since I care about her a lot. And I don't want to make things awkward for Simes and E-J either. I'll make my own mind up in the end, but still interested in the general opinion.