I'm in two bad relationships
I'm sorry to hear that. Why are your relationships bad?
Both of my significant others are cheating on me.
It seems that you are unable to keep both of your partners happy. It may be better in the future to be more monogamous.
I can't just break up with them, besides there is no trust in relationships.
Entertaining two relationships at the same time is unhealthy and will always lead to someone being hurt. If your relationships are toxic, you should talk with your partners about moving on.