Sexless marriage

So I’ve been married with my husband for 5 years now

At the start everything was amazing sex used to be every other day or at least once a week.

Now I’m 21 and he’s also 21 I’m a stay a home mum to our 2 year old baby after our child turns 3 or atleast starts school I want to start working again. But besides that my Husband works 5 days a week for 8 hours a day.

I talk to him about everything about our relationship about our future our childs future his mine and how he feels how I feel ect.

Nothing out of our conversation seems to add up to why’s he’s not having sex with me

It’s gotten to the point where I don’t feel loved I don’t feel connected to my partner and I’m really feeling like I’m losing feelings

I remember when we first met his sex drive was higher than mine now it’s the opposite.

I tried putting on a sexy lingerie in our bedroom I ask him for it he agrees then the second I start touching him he turns around to the other side of the bed and falls asleep within 2 minutes . So I just go to bed as if nothing happened often feeling ashamed for asking for it. He tells me now recently that he’s tired but he sleeps for more hours a day than me because I’m often the one doing all nighers with our baby especially due to his teeth coming out.

Please help.😞