Oh I can so so so relate to the threats of leaving. What suncather says is so true...how can they be so out it yet so easily work out our vulnerabilities???
Like others I used to beg, literally beg for him to stay, which he would...but made it clear that I was 'lucky' he did.
After 6 months of therapy I changed...and started with the 'off you go then' track. He'd always come back. Then I got to my rick bottom (almost) and wouldn't let him back and he's spent 2 weeks begging to come home.
Go figure...his fear of abondonment is as big as mine!