Anonymous wrote:OP, my suggestion is that you get a new nanny that has different boundaries. There are nannies out there who view their employment as more of a job, not have such a strong personal attachment and will not take such offense to your wife's request not to say 'I love you.' They can still be great nannies and care for your child, but will not love' your child the way the current nanny does.
This.
Your wife's reaction is unusually possessive and jealous towards the nanny. But there are other nannies out there to try out before she quits her career/job. She could try daycare. Daycare workers constantly see kids change and fewer at daycare show overt super affection on kids.
I personally am happy to see my nanny kiss and say I love you to my infant. I am not a first time mom and know I won't be displaced(?) long term even when at times my baby prefers the nanny hold him or something. As one of the PP said, you can be a crappy mom but no one will replace Mom in the kid's heart.