It’s easy for feelings to develop even when a stranger with chemistry becomes a Bull or Dom. It would be necessary to understand more about the relationship your fiancée had with her ex-boyfriend to really speak to the matter, but he seems like a dangerous choice for this role. We would seek out a handsome stranger as it won’t dredge up the old feelings (good and bad) and seems more likely to avoid unnecessary emotional entanglements. That is just my advice, proceed with caution either way.
JsCuck