I am not a fan of IC at all when a M is in this much trouble. IC is too often used as exit strategizing with the IC's blessing. They just want their client to be" ha-a-a-a-py."
Are you sure you mean "ultimatum?"
Ultimatums do work if you are prepared to mean it and walk when your spouse lies to you yet again. If you cave after issuing an ultimatum, you will never be taken seriously again.
I believe you should walk anyway. Four A's in seven years??? Yikes! And I'll bet there are more than is being admitted. There usually are.