I used to burn bridges for a living.
I think these days though, I make other people do all the work when it comes to ending contact. I don't actively try to disappear or ruin a relationship. Instead, I just mind my own business and get preoccupied with other things and people who actually give a damn.
People who want to reach out will continue to reach out, and for those people I'll reciprocate. But people who don't have me on their minds, much less their radar, will eventually fizzle out of my life. It's fascinating how little I can mean to people once I stop being the one to reach out first. Their memory of me dissipates faster than you'd expect.
Being forgotten hurts more than being hated. But it comes with the benefit of not inviting a war, and it doesn't require me to pull the trigger.