For instance, when we agreed to separate. I was literally sitting right there when she told her parents that we were separating for a little while, that it's not life-altering, that we just need to take a timeout from each other.
We go to the MC one time (11 days after she told her parents that) and she tells me that she doesn't think our marriage can work, she's as happy as she's been in years, and that "she's just done."
Here is how you SHOULD have replied to this: "I'm sorry you're done but I understand why you feel this way and I am glad you're happy now, because more than anything I just want you to be happy."
Because this response... "so when you told your parents that we were just separating for a little while, it's not life-altering, and that we needed a timeout....you were just lying?" ...is just awful. Not only did you insult her by calling her a liar, but you made it worse by saying it in front of another person. And you completely negated her feelings/ emotions in the process. Her feelings are REAL to her, even though they may change from 2 weeks ago to today. Your job is NOT to point out the inconsistencies in her feelings because she KNOWS they're changing. She wants support in what she's going through, not someone to tell her she's wrong or a liar because THAT is "more of the same" behavior that landed you in this sitch to begin with. When she talks, just listen and validate. Do not argue/ reason/ beg/ negotiate/ agree/ disagree.
