This isn't uncommon. Unfortunately in a triad you run into wo very distinct problems. When that love is never equal and two.. One person want to maintain triadic continuity. Meaning everything is about the triad instead of the individuals.
Te problem, or challenge is a triad is not one relationship. It's 4 relationships. The sooner everyone accepts and works within that knowledge the better.
The relationships are
This usually ends up happening when one person wants to hold onto their ideal. The original couple and the threesome only. Removing two potential and important relationships
The solution... Will the husband sit down and talk too. Can all three of you work through this. This isn't a you problem.. This is something you and the bf can work on with her..