Father As Groomsman?

My fiancé and I are at odds on who should be included as groomsmen. The issue is that my father (I’m the groom) has caused issues in the past and threatened to not come to the wedding and not welcome my fiancé at his house. Since then my parents and I have discussed the issue and talked about why they shouldn’t shut her out and so forth. My parents have agreed to come and support the wedding rehearsal dinner financially.


However, I also told them that my groomsmen would be my oldest brother as best man, my younger brother, and my fiancés brother. My mother pulled me aside after telling them that and asked why my dad would not be up there as a groomsman. I have forgiven my parents for their crazy behavior but my fiancé has not. Rightfully so in my opinion. My fiancé doesn’t care if her brother is up there or someone else but she doesn’t care to have my father up there after what he has said in regard to her not being welcome and so forth.
My question is how do I tell my dad that he isn’t going to be a groomsman? I believe that given his vocal disapproval my fiancé has a right to veto him being up there. But I’m unsure how to tell him and my mother. Any help would be greatly appreciated.