I'm in the same boat in a way. Hubby is an elder, which makes it very hard for me. Fortunately he believes freedom of choice is important but it has changed the dynamics of our relationship. I'm no longer the 'woman he married'.
I you want to keep together you may have to make some concessions. Could you accompany her to some meetings and assemblies, even if only one day? Let her know that your faith in God, Christ and the bible is just as strong. It's only your faith in men that has gone. She'll be feeling shaken and unsure, not knowing who you are anymore. Let her know that you haven't changed as a person. Try doing a family study with her but say you only want you to read the bible itself together, without WT publications. Maybe read the gospels or Paul's writings. This is what I do with my hubby, even though I have to bite my tongue sometimes when he comes out with JWisms.
It's hard, it takes effort and sometimes is very frustrating but it's worth it if you want to keep your family together.