need advice

talked to my girlfriend slightly one time about my fantasy of letting her be with another man essentially becoming a hotwife. it started out with me fingering her and while doing so telling her how good she looked and what other strangers who see her might be thinking. such as how hard they must be looking at her or how they may be thinking about fucking her. she didn't really respond much to these teases but her body did seem to quiver at each one. then i flat out told her that i would love to see her with another man and that it would be hot watching a video of her being fucked by someone else. she instantly told me to stop fingering her and seemed upset wondering why i would ever say that. to which she then was focused on the topic of an open relationship asking if i was just saying that to be with another woman to which i said no. long story short she seemed upset that i would even consider sharing her because she never once thought that way. but to me although my perception of it could have been off it seemed she wasn't completely saying no just more so expressing that she had no comfort in giving a yes. im just confused as to where to go from here i kinda backed out of the whole idea since her response.