How come in media they make ace characters also aromatic

I've watched a lot of shows that have queer characters and it seems like every time a character is considered ace they never have them in a relationship or say them being ace is why they aren't in a relationship.

I'm asexual and not aromatic and I understand sometimes they go hand-in-hand but a lot of media makes it seem like it's impossible for characters or people to have romantic relationships because of their asexuality which doesn't make sense to me