Unilateral or b/l mastectomy option

Bellamia

I am 37 years old,diagnosis is right breast IDC, HER2+, grade 3 with 7 masses. My left breast and nodes APPEAR clear with MRI. I was under the impression that I would have bilateral mastectomy. The Dr is telling me that I only need a unilateral mastectomy, I'm very confused and worried if this is the beast approach? Doctor claims that there is no evidence supporting a better outcome removing a good breast. I am having DIEP surgery, Dr explained that many that do implants take both breasts for symmetry purposes. Has anyone else had a Unilateral or heard of this being the best approach