<human>: Can you give me the gist of the text in a nutshell?

Moved in with this woman almost two years ago.  It started off okay.  She made an effort to be nice to my friends, occasionally helped me host parties, helped take care of my dog, was generally pretty all right as a roommate.  She did have some flaws -- using/eating stuff without asking mostly -- but those were minor and she'd make an effort to replace whatever it was.

Recently she's started to freak out whenever I have friends over.  She's feel like she's being ignored and constantly "hear" us talking about her.  It's gotten weird.  Some of my friends like her and try to talk to her.  She's often depressed so they are usually listening to her relate the latest crisis.

She's been getting over a friend of hers she liked for about six months now.  Rather failing to get over him.  She gets pissed that I won't listen to her talk about him the couple times she's tried.  She doesn't really have any friends and spends 90 percent of her time locked in her room doing nothing.  She used to practice on her guitar a lot but recently she's stopped and now I really think she does nothing.

I don't care enough to help her, but I also don't think she's such a bad roommate that I need to ask her to move out.  She pays the rent on time, still takes care of my dog when I'm away, is cordial for the most part, washes dishes, buys groceries, does chores etc.

She's just massively depressed, for ages, doesn't really have any friends, is always "lonely" or "tired" or "stressed" or "anxious" or some other negative thing, and mostly I just don't see her at all. She sits in her room and does nothing and I go out a lot, so it's not like she's a giant drain.  It's just kind of weird living with someone who doesn't seem to want to live at all and not being able to do much about it.
<bot>: What to do with roommate who sometimes makes me/my friends uncomfortable but isn't really a bad person or anything... just sort of "there" most of the time.