I'm uncomfortable with this girl, and wondering if I should worry...?

There's this girl that my bf is friends with who lives in a different state. He told me once that when she was drunk, she said that she wanted to hook up with him. Sometimes she makes comments to him on myspace that makes me feel uncomfortable. They either seem ually suggestive or flirtatious. I asked him to tell her to ease up, but she continues to call him pet names like "Big Daddy" and "my love". I'm pretty sure if a dude said stuff like that to me, it wouldn't be acceptable. I'm not jealous as much as I am uncomfortable. I know she lives far away, but isn't it respectful to refrain from comments like that when someone is in a relationship?