TLDR; Pretty sure my partner is taking advantage of me and that my relationship isn't real to her

Sorry for this rambling a bit, I just need to get this out there.

I blew up at my partner (who is also my fp) today. It's been really bad for the last week or so, with the prospect of moving in together and telling her daughter who I am. We are poly (a "V" situation, where she is married to her husband, and also has me, but her husband and I are not romantically/sexually involved), so moving in raises a lot of concerns. Better yet, we all have BPD.

During this blow up, I was having typical fear of abandonment due to plans she and I had being cancelled and her telling me she wanted to spend the day with her husband instead. 

I recently told both of them how I feel like I get the short end of the stick because of the situation being how it is. They have luxuries in their relationship I may never have. Such as:

1) I will never be able to legally marry my partner, and therefore, I can never have true legal rights/tax breaks/other benefits that come with being married.

2) They have been together for 6 years already, and have visibility as a married, hetero normative couple.

3) They've gotten the benefit of living together without having another partner there.

4) Her daughter doesn't know I'm her partner too or even that she is bi, but her daughter hasn't ever questioned their relationship (obviously).

5) I don't get to sleep next to my partner most nights, and in our one-year relationship, she's only started sleeping over for the last 4 months, and in those four months, she maybe has stayed over 10 times.

I can keep listing things here, but I think you all get the point. With moving in, I feel like I am the difficult one, but all I've asked is that we find somewhere where each of the rooms we have are "even." Like, I don't want to live somewhere where they have an enormous master bedroom with a decked out bathroom where I would have less. Furthermore, it's never been a question of who gets the master bedroom and who doesn't - it's always been assumed that I would have the "lesser" one. He is an attorney, and she and I both are legal secretaries. In our initial budget, we talked about how much we would each contribute, and their combined income was seen as one and mine as separate. The way it was discussed, it basically comes out to me paying $250 less on a per-person basis, but I've since gotten a better job, and I'm willing to bump up what I contribute so that we're all paying the same. However, I would assume that this means there is still no question of who gets the "better" room. It makes me feel taken advantage of.

Furthermore, her husband and her always comment on how he "has always fallen in love with lesbians" and "has a thing for gay girls." She is bi, and I'm a lesbian. I'm questioning whether or not I'm only here because he thinks it's hot, and the fact that they always talk about this makes me extremely uncomfortable. I'm concerned that our relationship is his fetish, that I'm only here to make their relationship better (being why I get the short end), and that all the things we talk about are fake (marriage, etc.)

I'm younger than them by far (I'm 23, she's 32, he's 39), and maybe that makes it easy to take advantage of me?

I thought I was devaluing them because I was mad, but I'm calm now and still see these things.

Can anyone comment on if this is normal to still feel all of these things AFTER borderline rage has subsided? Am I over reacting? 

I'm scared that I've wasted so much time pining over someone who is using me.