My situation was different but I will offer you what little I can. Personally, I think you owe it to yourself to see your T on your own for YOU! If your partner wants to see your T, he can make his own appointment. I agree with you that if he came into your session, he would only feel that you & T were both pouncing on him. Would lead to more conflict & you don't need it.

How does one live with it? No easy answer to that. I think it's different for everyone too. I was somewhat an enabler but also had to walk away and let the person fall flat on the floor before I came in to assist again. They just kept falling over and over again until finally...they reached the bottom of their barrel. You and he will know when that happens and only then will there be possibility for change. Until then, do all that you can for yourself and gently encourage your partner from time to time to take meds (it might just help them I'd say), seek counseling, find a job. Someday your words may sink in.