I know the roommate won't be a part of her life forever and ever amen, but is he avoiding hanging out with you guys because you want it that way or because he wants it that way?
If he's willing to hang out in common living areas with you two, why not? I don't think it would be a horrible thing to be attached to a person living in the same house. If you're doing things to purposely AVOID that, perhaps you should re-think it.
I have had some friends who I was very close to for a while and they were very much attached to my children. Due to moving or other factors, they're not around anymore. This is a normal thing in life. And yeah, studies may show that a two parent household is better than others, but you don't have that choice. And what about those cultures where men have several wives and the children have many mothers? Do the studies account for that?
I think the idea that your daughter is simply hungry for more people is on the right track. I also agree we project complexity where there is none. It could be as simple as she's seen you all day, let's play with this new guy. Know what I mean?
I'm sorry the business has petered out. If dd is indeed craving more people in her world, a daycare environment might be beneficial.
Your awareness of the need to deal with your circumstances is the #1 indicator that both you and your dd are going to be just fine. You make up your own normal and your own ideal.
As for this: "I have two job interviews this week and it's like how the hell am I supposed to keep up with my mommy duties, go out and find something to wear"...maybe some of our former WOHMDC'ers could help you out.