Feel like I never get a break

I don’t know what I need here advice or just to have a rant, but I feel like I’m drowning. I’m a SAHM to a 2 year old and currently pregnant with #2. My partner works long hours, 6 days a week and I am so exhausted with this pregnancy I honestly feel like my body is shutting down. I’ve resorted to letting our 2 year old sleep in the bed with me because he refuses to sleep otherwise. He is pushing every boundary that he can at the moment behaviour wise and also refusing to nap so I’m really in the thick of the ‘terrible twos’ at the moment. He kicks me all night long and wakes up constantly demanding things, then he’s up for the day at 5:30am some days, so I feel like I never actually get any rest. My partner does help when he’s here but the problem is he’s never here. It’s just me and our child 24/7, he’s never been to daycare and that’s not an option for us, I don’t have a ‘village’ or anyone I can call on for help. I have no friends. I know I’m wrong to but finding myself getting really bitter and resentful towards other mothers who work and send their children to daycare and get to have a break from it all in the real world. I love my little boy and I already love this baby so much, but I feel like I’m constantly copping more and more getting dumped on me and nobody thinks or considers my feelings, how I’m coping or how that all affects this pregnancy and this baby. My partner is a great father, but as a partner he leaves a lot to be desired. I feel like I’m drowning in this life and mourning the one I had before, I was such a free spirit and lived life to the fullest, now I feel like I just sit at home alone with my child with nobody to talk to or have anyone that cares.