My son's father is a fucking dirtbag

I'm so sick of this fucker. He cares more about the hoes he fucks then his own kid. I have 3 kids and my middle child has a different dad. He was concieved when my husband, who's the father of of oldest and youngest, were broken up. He treats my middle baby like his own. My son's father couldn't give af. Why I'm so angry is because my son's father was supposed to take him with him this coming weekend because I have a wedding to go to. I'm my sister maid of honor. We are going Friday, helping set up some stuff Saturday morning. Have the wedding and our flight home will be Sunday morning. My son does not want to go because we are all staying at the farm and my middle baby, bless his heart. I love him so much. He has certain issues. He doesn't have low self esteem. He has NO self esteem. He's very shy, which is why he hasn't made friends at all and he's already in the 8th grade and he sometimes has problems at night. It's not nightly but enough to where it's embarrassing. Nobody is mean to him about it here. He just puts his bedding in a corner and me or my husbands gets his stuff and washes it. But people in a house full of people made him nervous about that and just nervous in general. And a hotel isn't an option sadly. He asked his dad back in APRIL! If he could stay with him that weekend and he said in text "Yeah son that's fine!" His dad knows about his issues. His dad has been hyping him up. Saying they're going fishing and out to eat. Blah blah blah. And he texts ME. Not even his own son. ME! And says "Sorry. Can't get Zayden this weekend. Unique wants to spend time together". Unique is whoever he's fucking now. I told him he needs to tell his son that and he left me on read. Then I told him he's a pathetic excuse for a father and he's trash who doesn't try to get better. I'm so sick of him getting his ONLY child's hopes up just to break his heart again. Like why even promise and keep hyping him up. Now I don't know what I'm gonna do. He's a POS ugly ass mother fucking excuse for a father anf I'm sorry. I know I sound so immature. I'm just so fucking pissed. I can't fucking stand this motherfucker!