Thank you for your reply! Firstly, not breastfeeding or reducing feeds is absolutely not an option. To be honest the suggestion is insulting given the benefits of breastfeeding. Shared care, even in the long term is also not an option as I have 2 other children and will not split siblings, and even if I was open to it, (which I'm not) we live too far apart for that to work logistically when she is school age.
I have also never heard of a 5 month old going overnight to dads and know legally there wouldn't even be a chance of it being enforced etc until she is at least 2.
I will continue to do more research though on what is best. I don't want to damage their bond but I have a lot more to consider. I also have to consider her siblings and their relationships as well as wanting to limit ex's contact with my other dds.
I do actually have a psychology degree myself and had always followed attachment parenting techniques when my babies are younger. Attachment theory disagrees with quite a bit the above in that infants are only capable of having 1 primary attachment figure in the first 12 months, and damage to that relationship is catastrophic to their development for the long term-insecure attachment, avoidant attachment all damages relationships in later life etc. Im unsure that less time with her father at this age will do any damage at all.
In saying that I do believe he will be a great dad, and I will be fine with overnights when she is 2/3+. I may suggest he takes her outside my home for his visits if that will help.
Definitely food for thought!