I have not used ITR but it is supposed to be something a bit like EMDR in that the techniques are meant to directly influence the traumatic memory and re-structure it. Effect the brain more directly than just talk therapy, they believe it can be achieved via expressing the story in some artistic activity, for example, and piece a more coherent narrative together. IFS is more talk therapy with a symbolic system to understand the person's different needs, motives, avoidances etc. In general, if something sounds too good to be true, it probably is... But just like many people find EMDR helpful, perhaps ITR can be as well. I would not expect it to make a huge difference but perhaps it is worth trying, especially if it does not take long to see if it helps or not.

As for the loss, maybe find a support group of peers with similar background that meets (or is at least available) often? Might even be free.