you're in the power position. haven't been accused and you're not cheating. It'll keep her on her toes - just let her stew instead of being the other way around. Better to work out the trust issues ASAP - and yeah, you're not married - and unless it's a truly committed relationship - ain't nothin' really holding you back from shopping around. Let her know that respect is a two way street and she must earn yours just as much as you must earn hers by being casual about it - and just asking for proof if there is such as accusation. "what do you think?" is always a wonderful question when used with the right tone of voice