I think he has a romantic view of her because he knew her when she was 17. And his marriage had just broken up badly (woman was physically abusing him), and songspell walked in at the right/wrong moment.
I used "dating" to indicate that it began as a purely virtual relationship. She had these relationships for more than a year, and had visited people several times before she moved here.
As far as I know, Sanginist is entirely committed to our relationship- but he's also committed to theirs. (Though he has mentioned that he knows that if they broke up, it would be explosive and dramatic, and that if we did, it would be well- communicated and we'd both know what the real problem was.)
As for why she would not have her own place, apparently she recently had her work hours cut. As for why she can't have roommates that she's not involved with- I have no clue. I don't think she knows all that many people here.
I would say that her current housemates are the type to take advantage of someone trying to help out. One of them has back problems that sometimes leave her incapacitated, and her husband is the kind of person that gives a child a toy and expects him to be fine for an hour of so. Yes, she just needs to stand up to herself, but I don't know all that much about the situation.
Thanks to everyone who replied- and I hope that I can make this work for as long as it takes him to figure all this out.