Wife confused...i'm confused...Divorce probable?

[Jim]

My wife and I have been married 6 1/2yrs, together for 8. Been through financial ups/downs, foreclosure, death of her mother, death of a dog, baby, school, etc.
I finished 6months of school last year this time frame, and was not working. She was working TONS to pay bills. We faced Divorce then. Found out she was preg. and stayed together. I began working, everything was good. Had a healthy baby boy. She went to school to finish and was always gone. I tried to get her to stay home more to spend time with the baby and I. I backed down from work to take care of our son, with her approval. A month later, i'm still out of work and bills are piling up. She takes and fails a test last week, and I try to make her feel better. Goes downhill fast. Now we're facing divorce again.
she claims to still love/care for me, but not happy in the marriage. Wants to separate. after soul searching of my own, I asked her to stay. She did, but still wants it. agreed to counseling. she wanted sex yesterday?
why would she complain about meaningless sex, then as things are still shakey, tell me she wants sex? she said she needed a stress relief...but now i'm wondering if its a good thing/bad thing. i dont see how this helps anything.
ps- she doesnt say i love you unprompted 80% of the time now. i know its only been a week, but the next day from beginning this spiral, she did...now nothing.