I don't really go to my therapist for advice and when she does give it, it tends to be in a pretty vague and non-directive way (eg today she said maybe it would be worth scheduling some fun and down-time for myself to help feel less depleted). I don't think I could stand it if she told me how to go about my marriage.

It's a pretty bad therapist who is a) deeply attached to the outcome of your marriage and b) cannot separate their experience of getting divorced or staying married from the client's circumstances. I would leave if they were communicating to me that I should make the same choice that they did.

I know my therapist is currently married but I don't know if she's ever been divorced.