I have this problem as well. And it affects me greatly. As a sort of workaround I've taken to considering a death which takes the form of an accident. They will still be in pain; that's certain; however it could be lessened by some degree, as far as I have learned. I'm not sure how much it could work, if it works at all, but this way there's the potential to reduce the feelings of guilt along with suppressing the question of 'why?'. I've seen these two to be the most outstanding emotions felt by those who've lost someone to suicide. They feel a lot more it's just that these two are often referred to as "the worst part". It's not a whole lot but I feel like if I made it look like an accident it might make it less painful than if it was totally known to be a suicide. Though that is an extremely difficult thing to pull off comfortably.