Help me help my marriage

So to tell you guys a little, my husband & I have been together for 3 years, married for 2. We have a 2 year old son who still sleeps in the middle at night so we don’t even touch in bed. I am 4 months pregnant right now with baby number 2 & I’m just super exhausted! We have a quickie every now & then (maybe every 3 weeks or so) but I just need some tips on how to get my sex drive back?! Maybe the start is getting my son in his own bed, which he has one but I get so worried about him in his own room away from us 🤦🏻‍♀️ I’m stuck between feeing guilty about not having sex with my husband, & not wanting my baby to sleep away from me at night. My husband thank god doesn’t push me about anything he tales what he can get & doesn’t complain, but I feel like I am causing a disconnect. I have gotten such a low sex drive since being pregnant. What do I do?! Anyone have experience with this? Just want to add that we both work 40+ hours a week which is exhausting for me also because by the time I get home my sciatic nerve is killing me, my eyes will barely stay open, & I just want to lay down. It’s horrible guys I’m losing myself