conflict with sexuality?

Hello !! So.. I am on the asexual spectrum and it isn't a thing that I doubt or have had conflict with before, I have always been relaxed about that. But a while ago I was talking to someone that I used to date (we continued being friends) and I did a joke about being confused about the "importance"of having sex. but I was just joking like usual, I knew it was going to be chill, she's bi so she obviouslly doesn't have a problem with sexuality,the thing is the conversation kinda developed on that side and she was like, wait you are asexual (which to be honest I don't even know Haha ) and we kept on talking and she started saying that it was so much harder to get a couple, I told her I knew but that I still wanted to find someone to be with, and she asked me if I was ok with my couple being my parnter but having sex with other people and in the moment that made me very mad, because she told me that if not, it would be very very hard to find someone, I got deffensive and told her that fine I'd have sex even if I hated it just to make someone happy. And well I don't know if it was because It was her, because I'm usually chill with that kind of things but now It really has stuck with me. even If I am open to more "free" kind of relationships, If I am with someone I don't want them to be with other people especially if we are together and the only reason is the sex. like I just want someone to luuuv, and well I guess I could accept it and just go with it and it is just letting a little of my comfort, but I do feel like in that scenario It feels like it just makes me less lovable?? like I don't get it but ok .

but for real I have been thinking about it a lot and I could use anything you want to say to me, to be honest also I really want to know, If there are any asexual people that have been on relationships like that, it really doesn't work?, how do you handle it?, is it hard to find people willing to date you? does it represent like a problem ? and i don't know, anything I guess if you have any experience like that ....so... thank you if you could help me hahaha aand yeah that's it

(Also I don't know if this is how you do forums I'm new to this so, sorry just in case. And excuse my bad english)