I think your husband might have a point, Jean. I've had friendships fade away (not my choice) in the pass because we were in different places in our lives--a more successful career, a happier relationship.
Although we might tell ourselves, and even believe, we're happy for a friend's successes etc., if we're not feeling great about ourself, it can be hard to feel close to, or feel much connection with someone who seems to have it altogether.
Just a thought. I sympathise with your plight, it sounds as though you've done your best to keep the friendship going, maybe it's just time to let it go. My best wishes.