AITA for moving to another country while pregnant and "kidnapping" my husband's baby?

I met my boyfriend 4 years ago when we were both working for the same company in Japan. He is Australian, I am Italian. I've been living in Australia for the last 1.5 years. I am here on a partner visa.

I am currently 3 months pregnant and I thought we were both happy. However, I only just found out that he's been having an affair with a coworker for the last 6 months. At first he denied it but I had proof so he changed to begging me for forgiveness and that we could work it out and all this bullshit. But I don't want to. I'm done. I don't want to be with a cheater. I broke up with him and already moved into an Airbnb. I'm planning on going back to Italy because I have nothing here apart from my pos ex. I let him know today. He flipped out and told me I can't do that. He said I'd be kidnapping our child and that I'm not allowed to leave. But I've made up my mind. I already talked to my parents and I can live with them until I have figured everything out. I'll likely get my old high paying job back so I'm not worried.

However, all of my ex's friends have been texting and calling me all day saying I'm a pos for stealing his baby and that they will take legal action. I don't think they can and I wouldn't be allowed to stay anyway since I'm on a partner visa and this partnership doesn't exist anymore.

AITA for going home?

Update:

Unfortunately the mods wouldn't let me post an update post but I'm hoping that some of you still find this if you are interested.

Many of you wanted an update so here it goes.

I left Australia the day after my first post and I'm in Italy now. I'm staying with my family. Thanks to the good connections my friends have I got a good job at the very company I worked for before I moved to Japan.

At first I thought I'd keep the baby but after a lot of thinking I decided I would abort it. It had to happen rather quickly as I was running out of time so I had the abortion today in Switzerland. I'm doing okay. This morning I sent a text to my ex letting him know about the procedure and when I checked my phone after it was done it was full of missed calls, texts dripping with abuse and threats that he would come to Italy to stop me. So yeah I made the right decision. Nothing ties me to this man anymore. I feel weirdly free but numb at the same time. But I'm determined to start over.

Lastly, I would like to thank everyone who sent me encouraging messages or even offered their help. I do really appreciate this so much. I hope you understand that I didn't message you back but I was so busy getting out. I will forever remember the internet strangers who were willing to help me out. To the people who called me a whore and said the world would be better off if I got hit by a bus, I forgive you.