My son (5yo) is scared of his Dad

TL;dr: my ex hurt our 5yo son, so I left him. Son is now scared "all the time", doesn't want to visit his Dad, has aggressive outbursts, and has started bullying another child. I've called a helpline, followed their advice, and am in the process of taking my son to a child psychologist. I'm not sure what else to do, any advice would be appreciatedI'll try to keep this brief, although there's a lot that's happened.My partner Ben (28M) and I (27F) separated a few months ago. We have a 5yo son, Jack.To give you a picture of our relationship: I was constantly nagging him about parenting and housework, and doing all of the organisation for our lives and my son's social life. He would sleep in until 10am, go to work, come home and play video games all evening (according to his Steam profile, he's clocked 1000 hours/year of games, for the last 7 years). If I asked him to do something he would do the bare minimum (e.g. doing the dishes = loading the dishwasher and leaving everything else).When it came to parenting, we had a lot of tension around bedtime. Jack fought bedtime hard. It took 2-3 hours every night to get him to bed, he'd fight every step of the way. I usually helped him brush his teeth, put his nappy on, read a bedtime story and cuddle in bed. Then he'd start getting out of bed and running around the house. Ben and I would take turns carrying or walking him back to bed. Ben would often get frustrated and carry him roughly to bed, then Jack would get up and run to me because he was scared.One evening he came home and decided he was going to put Jack to bed. Jack was standing on my bed talking to me while I put some laundry away. Ben grabbed him by his arm and pulled him hard off the bed so he fell onto the ground. Seeing him hurt Jack like that was the last straw for me, I slept in the spare room for the next two months until Ben found a new place. I completely took over the bedtime routine, and told Ben to take a walk and not be here at bedtime. I called a good family friend to visit in the evenings and help. From that point on, Ben barely spent any time with Jack at all.After Ben moved out, Jack got so much happier. Jack even said "thank you for leaving" to Ben on the day he left. The bedtime routine went smoothly, and now takes about 30 minutes from start to finish. There's no stress, fighting or drama.Soon after Ben moved out, Jack told me that when Ben put him to bed he would "squoosh" him so he couldn't breathe. I asked what he meant and he said Ben "squooshed me with his body so I wouldn't get out of bed".Jack is scared to visit his Dad's house, and will only go there is his grandparents are there too. The last time he had a visit, he told Ben he wanted to walk to the park, but then he walked back to my house (about 2km, Ben was with him). I got home from the shops to see him sitting on his trampoline in the yard, and he refused to go back to Ben's house.On the days close to visiting Ben, Jack gets very anxious and aggressive. He'll hit and kick me if I try to set a boundary (e.g. one cup of juice with breakfast, not being allowed to visit a friend's house because we have plans already). He tells me he's scared all the time of being squooshed, and almost every night at bedtime he asks "why did Dad squoosh me?" and "why do I think about being squooshed all the time?". I don't bring it up. He's also said "I used to love Dad all the way to the kitchen, but now I love him this much because he squooshed me" (he holds two fingers up with a 1cm gap). For every other relative and close friend he says he loves them "all the way to all the planets and all the solar systems and infinity".I've called a family violence helpline to get advice and get in touch with some services. They told me that Ben has a right to see Jack, and that I should talk to his grandparents about helping with visits (done). They also gave me some information about local parenting classes to pass on to Ben (done). The impression I got is that because Ben has never caused a physical injury, they didn't think it was that serious.I've made an appointment with Jack's GP to get a referral to a child psychologist. I explained to Jack what a child therapist does and he said "I want to go to the special doctor, so I can stop being scared all the time".Jack has also started bullying a younger child at preschool, he chases him, excludes him from play, and yesterday he told me he built an "Alex killing machine" with blocks. He often threatens me at home too, saying he'll hit or kick me, he'll put me in the bin and call the garbage truck to come and get me, and once he said he would kill me when I asked him to turn the TV off and come eat dinner. (He's not a screen obsessed kid, he prefers to play with cars or trains, or go to the park). The threats and anger are when I won't let him do something he wants to do.I don't threaten him, but I do explain consequences. I wonder if he's interpreting them as threats. (E.g. "if you don't brush your teeth, you'll get holes in them" and "if you can't play safely with your toy, I need to put it on the shelf", although I'll only say things like that after asking kindly a few times)Has anyone had any experience with this? I want to help Jack with his fear, trauma and aggression. There's going to be a long wait to see the psychologist, so I want to figure out some techniques and tools to use in the meantime. Any parenting book recommendations would be great too.Thank you for taking the time to read all of that. via /r/Parenting https://ift.tt/2LlorY9