Stress & pregnancy

Exactly how bad is stress for your pregnancy? I'm 20 weeks, I have a 2 year old, and a son that JUST turned 1. I'm a SAHM and my SO travels a lot out of state for work, he's currently home from California (we live in Indiana) for another week or so until he has to go back. Since He's been back he hasnt been much help and this isnt new, I get that he's been gone working but its like he's gone all day everyday or in his garage working on something all day only coming in occasionally to get a drink or something, yes, I've talked to him, no it hasnt changed and I'm worried it never will and we're already almost 3 kids in. He screamed at me for "not taking care of the house" it's a little messy today because its only been me doing everything by myself and yesterday I had an appointment and was just exhausted so I played with the boys and we mostly just had a chill day and watched movies. He doesnt think I have anything to be tired about. I'm small and when I'm pregnant its like it takes it all out of me, on top of that I'm anemic and findinghthe energy every day is so hard sometimes. Today I feel like its been non-stop running around after the kids, I hate raising my voice at them but it seems like thats all thats happened today and I feel terrible. I started cramping pretty bad so I tried to just sit and chill out for 5 seconds but its hard when I have no help and two small kids. I'm so scared for the 3rd baby to get here, I just want things to be good but our relationship is going downhill, he's never around and when he is he still isn't if that makes sense. I'm venting, maybe someone out there is going through something similar, yesterday was my birthday and he was still gone most of the day, a happy birthday was all I got. We didn't spend any time together and the kids and I went to bed a little early. He'll sometimes say we can come outside with him so I'm not in here alone all day but when that happens he ignores us and its just me chasing the kids around and its been so hot here recently its just not enjoyable. At this point it almost seems like it would be easier for me to be alone rather than be with him. all I asked him to do tonight was make dinner, I got everything out and its 7 and he still hasnt started, on a happier note my 20 week scan is coming up where I'll find out the gender ♡ I'm really hoping for a girl this time 🤞🏼 if not, pray for me because these boys are crazy and I know 3 of them will be chaos lol

EDIT- A fantastic text I just received. I'm trying not to flip, he was just in the house and saw my 1 year old screaming his head off because I walked into another room and then leaves and sends this.