He might be feeling overwhelmed and sometimes people de stress with “me time” while you should respect him and his time alone it doesn’t give him the right to neglect your relationship. Tell him to communicate when he needs time alone or ask him how he would like you guys to spend time together. Everyone reacts to being new parents differently my fiance and I definitely went through this and it’s not gonna fix itself over night but it’s gonna take a lot of communication and understanding on both parts. 🫶🏼
Communication plays a big part in a relationship especially when a child gets added to the mix. See if this is something you can work on together or maybe mention therapy with each other and or individually. Always here if you need to chat!
I'd say start by making a "date night" maybe someone can watch your kiddo for a bit. The two of you can have just two of you time.