H's apathy is far worse than anything else he could have thrown at me. Anger would at least show he still cared.
From H's perspective he has a job he loves, has someone who makes him feel good about himself (and like he is the only person that matters), a good circle of friends and a good lifestyle. Coming back here, means not only coming back to me (someone he no longer loves or probably even likes anymore), a marriage that would take a lot of hard work and effort with no guarantee of it ever actually being happy, no job (his job is very important to him), the reality of life with its many day-to-day chores and errands, and no close friends nearby (living in a university town a lot of my H's close friends have since moved away). I can appreciate it is not an appealing prospect and, if the situation was, reversed and I didn't feel so strongly about not divorcing/always being committed no matter what, I would also probably try to hold onto my new found happiness like grim death.