Long Post Warning

In January 2017 my dad died. It was hard on everyone since it was so unexpected & we really thought he was getting better. It was a lot harder on my sister & I because all three of us spent so much time together. My mom was never really in the picture. My parents weren't divorced or anything, my mom just picked everything else over family time. February 2017 my mom gets a boyfriend, who just so happens to be the man my father accused my mother of cheating on him with. I was pissed but didn't want to get into the middle of it because I was grown & none of my business. April 2017 I find out I'm pregnant. My mom absolutely flips her lid even though my boyfriend & I were homeowners (at 20 & 27 years old) & had stable income. She didn't talk to me for two days after I announced I was pregnant. After the two days she started a ritual for about a week of calling me to see how I was feeling. Now she doesn't. Any time I try to talk to her about the baby she just seems very disinterested. She was never like that when my older sister was pregnant. Losing my dad still hits me pretty hard & I miss him everyday. But when I have really bad days & cant breathe because I'm crying so hard I call my mom. "I miss him so much." I'll say. Mom will just reply with an annoyed sigh & say "Carole, we all miss him. He wasn't going to get any better". I can tell when she gets annoyed with me so I just end the conversation. Any time I bring up my father around her new boyfriend she gets mad at me. She'll roll her eyes or just give me "the look" (the if you don't shut up I'm gonna whoop you look all moms have). My boyfriend is really good at talking me through my panic attacks or those episodes where I cry so hard I can't breathe but he gets overwhelmed when they happen a lot (like they have for the last week) so I try to turn to someone else to give him a break. But I just have no one else. My sister is a nurse & is always working so it's hard to catch her but she's usually so stressed out from work that I feel bad about throwing all my problems at her. I don't have any friends, we moved 3 hours away after my dad died & we don't really get along with any of our neighbors... I just don't get why my mom doesn't care... am I just being selfish or did I do something wrong? I don't understand.