Not to keep you away from your focus, but I don't think that WS or narcissists have the inside track on control issues. Although I have not had homicidal thoughts toward my H, I have struggled most in this situation in areas around control. Several times on hearing things he did WITHOUT CONSULTING ME I was either furious or sobbing and screaming uncontrollably. It is sad to me in retrospect how much value I have placed on control.
I don't believe that love ever leads someone to kill. Instead it is that something dark inside of each of us that can be tapped under the right (wrong) circumstances. For example, would I kill someone that I thought will kill, rape, or subject my children to extreme bodily harm? More than likely and I am by no means a violent person. In the DV incidents in which I was involved as a lawyer, I witnessed issues with control, loss of control, and an attempt to establish control.
The fact that he killed himself is entirely understandable and Many of these types do the same thing. It is simply another way to maintain control over the outcome (prison, dealth penalty, suicide).
I completely understand your feelings toward him. This wasn't some statistic. This was a living, breathing person whose pain and suffering you were witness to.
Now, you've stated a goal to move on from remaining stuck, how do you get unstuck (of course I partly ask this for myself). I made the decision to press for the separation contract knowing it would result in divorce talk. I still spent the next two days sobbing and shaking from the reality that I am closing this book and letting go of those last strands of hope that keep me tethered in a very unhealthy way to this person who has harmed me and my children so much. I have even been obsessing over the fact that he seems to be gathering things for a party (perhaps 4th of July?) when he would never allow me to have people over, have friends for that matter, and certainly never throw a party. Part of me says who cares. The other part is infuriated.
Have you ever read Pema Chodron? I think she is a huge help with "stuckness".