Is there really no sexual attraction/chemistry between us?

I recently discovered (1 week ago) my wife's emotional affair with a guy on facebook. She wasn't getting the emotional support she needed from me, so she turned to someone else. I don't think the affair went much further than flirting and daily conversation for a couple of months, but now she says there's no sexual chemistry between me and her. We've been together for about 16 years, married for 9. Up until a week ago we were having sex 2-3 times per week. We have small kids too, so it's rare that we get a couple hours to ourselves, except at night after they are in bed. I thought the sex could be better but my wife says she just put out to keep me from getting angry, that it was easier to simply have sex than deal with my frustration if we didn't. She says she was never sexually attracted to me and that we have a passionless marriage. The sex was usually so so for me, but I do remember times where she initiated and it was great. It's absolutely crushing to hear she is not sexually attracted to me anymore - and I can't live with someone who feels that way. We had our first marriage counseling session, and things are still very weird between us. Is it possible her attraction to me is temporarily tainted because of the emotional affair - or are we doomed to a sexless marriage if we choose to stay together? Right now I don't know what to do, a week ago we were having regular sex, now we sleep in separate beds and cannot even touch eachother. I can't keep this up for much longer (no pun intended). The counselor suggests a three month process.