Oh my goodness. Maybe she has postpartum anxiety. I know I can relate to the behavior you're talking about. I had such anxiety even when someone came over and watched the baby in another room while I showered or napped.

I don't want to make excuses for your wife. At 8 months post partum, baby should be on solid foods and able to drink from a cup, in other words, a bit less of a worry for someone to babysit so you can have a date night.

Maybe there is a new mom support group in your area or counseling available for someone who is privy to post partum depression/anxiety. Please ask her to work with you on this. You understand having a baby is a game changer and that she is looking out for baby, but you need to find some way to reconnect with her; some type of compromise.