Go with your gut instincts mosschops.
Or if you feel you just can't bear to leave him yet, why don't you wait another year to go back and study, surely a year off won't make a huge difference.It sounds to me like you seriously don't want to leave him with anyone yet, so do you think you could do all of the work required if you're leaving him but are seriously unhappy?
You probably know in your heart what's right for you both.........