Marigold is acting like a teenager, so Hanners is treating her like one. Notice that she's not fighting the grounding--she knows she needs it. She's irritable about it, but on a deeper level, she knows that Hanners is taking care of her.
Honestly? I'm a lot like Hanners in certain ways, and I would probably do the same to a friend like her. My best friend is a gamer, too, but he's usually a lot happier being around people and being outside. Gaming is good. But when you don't have much else to do, you go insane. This is truth. Marigold needs this intervention. Remember how much fun she had when she was offline? She enjoyed being around people and wearing a dress and being called pretty. If Hanners can get through to her, then she'll be much more apt to strike a balance between gaming and having an offline social life. Sometimes, people need tough love in order to see that they're being self-destructive (whether they're cutting, saying suicidal things, feeling sorry for themselves when they have people who care about them, or spending too much time online). I'm always more than happy to dispense tough love to my friends when they do things like that. And they're always proud of me for saying what they actually needed to hear because it makes them feel better and reminds them that I am not a doormat, that I can be their mother and friend when no one else will be honest with them.
Also, WoW is a social game. While it seems she doesn't have a lot of friends, I'd be willing to bet that she's made a lot of friends in her guild through working together and just chatting when they're not in a raid or instance. So do keep that in mind.
Still, she needs to get out more, and she knows it. She wants to go be around people, but she's not sure how to go about doing so. It's a hard transition, and Hanners has been through it and knows how to help her out.
Just let the characters do what they gotta do. It may be appalling or offensive to you, but this is what needs to happen for the characters and the plot. I speak from experience.