Am I right to be upset or am I just jealous?

So, for a little backstory my father died in January 2017. My mom, a month later, starts hanging out with the man she cheated on my father with a few months before him dying. They of course start dating & that's when my mother starts ignoring me. I live 3 hours from my mom which just so happens to be the same town where her boyfriend has all of his doctors appointments. I live five minutes from his doctors office. Mom has come into town, told me she's in town & when I ask her to stop in to say hi she always comes up with an excuse. June 30th, I get into my first ever car accident. Mom drives up & stays the night with my boyfriend & I to make sure we're okay (I was 14 weeks pregnant at the time & very shaken up, went to the ER to get checked out & everything was fine). She leaves on July 1st after taking my boyfriend & I grocery shopping. July 2nd I find out my car is totaled. I need to get a new one & my insurance company won't pay for it & neither will the other drivers insurance. Mom comes into town a week later. She calls to tell me she's in town. I ask her if she could please take me to the store (that's a 5 mile walk) to pick up a few things for the house we need. She says, "I can't. It's too hot up here." She leaves town. She stopped telling me she was in town after that unless she wanted to stop in or wanted me to take her somewhere downtown (she hates driving there). I call her the other day, having a complete emotional break down because we can't find another road worthy car in our budget, none of our neighbors (whom we've never gotten along with any since moving here in April) will give us rides to the store or to my prenatal appointments, I was having a really shitty day & was missing my dad a lot, etc & she says "I'll call you back I'm at Lenard's*". (*Name changed for privacy). She never calls back. My boyfriend sat with me in our bedroom for a good 2 hours while I did nothing but cry until I eventually just went to sleep. Mom didn't call the next morning either.

Ever since she got with "Lenard" she's put me & everyone else in her life on the back burner. I realize that I'm 20 years old & that mommy isn't always going to be there to help me but I'm also just starting out on my own with my boyfriend, pregnant & all alone in a big city with no friends or close family. Even my sister who lives out of state noticed her changing & putting "Lenard" before anyone. She's even canceled FaceTime dates with her 4 grandchildren because she was with him. I feel abandoned in a way. I want my mom to be happy, I really do. Am I right to be angry or am I just being jealous??