My suicidal ideation was the same thing, and I just mentioned it in my last post. It was an extremely violent fantasy. It was never to be carried out, with time I realized why: because I couldn't do that to my mother, as it would destroy her. So I found love through violent fantasy. And now I love bike rides in nature and kittens on Youtube, among many other things.
Habits can become addictions, they can cause problematic behaviour, and we can wean ourselves onto something else to displace the addiction. If your fascination with violence spills over into your behaviour in any way, starting with unreasonable or counter-productive expressions of hostility, then I would say that's a warning to you that the fascination is becoming problematic and it could end badly for you.
What non-violent things do you love, and can you increase your involvement with them?