In what ways should you trust a lifelong significant other?

I broke up with this guy once and one of his female friends asked me why. I told her that I couldn’t trust him. She freaked out and said “He’d NEVER cheat on you!” But I didn’t mean that I thought he was cheating on me. That never even occurred to me.

What I didn’t like was his financial decisions. I thought they were terrible and potentially dangerous. I also didn’t like that he refused to consult me before making major decisions—like extremely invasive but totally elective major surgery. I thought if I got together with him, he’d wreck my own finances along with his and leave me out of the loop when making major decisions—like up and leaving the State and forcing us all to relocate on a whim (which he ended up doing to his current wife)

Anyway, I am surprised that for many single people, trust seems to be all about and only about whether or not someone will cheat on you. So what else should you trust someone about?