Welcome to our forum.
Sounds like you're giving things some time and not rushing into anything, which is wise. I'm a little concerned about your husband's currently-celibate state, but I suppose that's for him to work out if you know you're not sexually compatible with him (and can't be).
I'm in an MFM V (basically the same set-up you have) and we all live under one roof. Each of the guys has their own bedroom. I have an attached bath (which is a lifesaver for me). The lady of the household basically alternates (from day to day) which bedroom she'll sleep in.
She and the "other guy" don't have much sex, but some. She and I make a point of having sex once a week, which really works for the (unhurried) speed of our libidos. We have polyfidelitous rules (no sex outside our three person circle, and if we ever add a fourth person it'll be a mighty slow, careful process), but your V may be a little more easygoing about adding people and what can be done on dates. It's all about what works for you.
I hope things go well for the three of you and that having your boyfriend move in will prove to be good for everybody. Please keep us posted and ask us any questions you have along the way.
Love means never having to say, "Put down that meat cleaver!"