You are not the issue. No one is to blame for depression.

It doesn't seem like your husband's depression was necessarily triggered by a situation (or at least a major external situation). Am I right? Unfortunately, depression doesn't need a big (or any) trigger sometimes. It's so frustrating that that is so often the case.

You say that when your husband's mood improves that everything improves, even for you? That's good.

Do you go to therapy, too? If not, maybe you should consider doing so for a bit, and your own therapist.

It's true that during depression many people isolate or seem to be distant. That's part of the illness and doesn't reflect on anything a loved one or friend did or didn't do.

I'm sorry your husband has to wait so long to see his psychiatrist. Support in between may help. Have you heard of NAMI or DBSA? They offer free support groups. Maybe there's one in your area.