So exhausted

My baby is waking up every half hour lately, day and night unless I hold him, I don't know why. My husband is working so much I hardly see him and only watches the baby an HR at the most at a time to give be a break, and then makes me feel guilty constantly saying he has work to do. I don't have any family or friends that I feel comfortable leaving him with so I can run out and get some RR. when my mom comes from out of state she offers to watch him so I can go somewhere or just take a nap, but then I feel guilty I'm not spending time with her so I don't go anywhere or I lay down and cannot sleep. I finally broke last night and told my husband I cannot do this anymore. I never sleep, I don't get help. He laughed at me, thinking I was kidding, rolled over and went to sleep. He literally thought I was kidding. I feel like I'm slipping into ppd and I feel I can't get out. I'm listening to my baby scream right now, with tears streaming down my face, because I just can't calm him and I feel there's nothing I can do. This is nothing like I thought it would be, and all anyone says when I try to reach out is, "this will pass". Or "thats just normal and you have to deal with it"