Do you think I can ruin a relationship?
Do you have a good reason to ruin it?
I just want to ruin something that's not mine
It is hard to see others happy in their relationships but you shouldn't interfere in other people's relationship and ruin it for them. People will think that you are a miserable person and not want to be around you.
If it hurts more people I don't give a shit.
Wanting to hurt people on purpose is selfish. If no one has done anything to you there is no reason to ruin their relationship. How would you feel if someone intentionally tried messing with you and your relationships?