(((flygirl))) - I'm so sorry for your loss. Though most of us go through the guilt period, I'm an RA and I can tell you that nothing anyone said or did would have made a difference. I left my XABF#3 as he continued to smoke crack (my DOC). The few times I had contact with him, I was supportive, told him how recovery had made such a huge difference in my life, but he didn't want to stop. He died at the same age as your XAH.
I hope you continue to reach out here, and have f2f support. There are stages of dealing with death, and we go through them differently, and it really helps to have that support.
Hugs and prayers,
Amy