By labelling it correctly: another act of abuse.
People with consciences don't commit abuse. People who love you don't abuse you.
I know it's still hard, and it will hurt for a while. But you will come through it. You don't need to instantly be over it, or consciously wondering how to get over it. It's something that will happen naturally if you focus on building a stronger, better happier life free from abusive men.
I honestly think he's done you a favour though, and it will help to focus on that. If he reappears please don't take him back - he will then know he can do whatever he wants to you and get away with it, so his blatantly abusive behaviours will become even worse.
Have you found your anger yet? Anger would be good here, it would show that you recognise you deserved better than how he treated you. And that would stand you in good stead for your future.
You're very young, so obviously even younger when you got into this relationship. That will probably make it feel even more painful, but it's worth remembering that you still have your whole life ahead of you to break this pattern and build something better for yourself.
Him leaving has given you the opportunity to meet a decent human who will never abuse you. (There is no such thing as a slightly abusive or intermittently abusive relationship, just that we haven't identified or recognised the rest of it. Men who abuse us do not love us, no matter how much they say otherwise - abuse is not compatible with love.)
I would recommend you go on the Freedom Programme. It will help you heal from him by teaching you how his decision to do this fits into his pattern of abuse, and show you what a healthy relationship looks like. That way, it will give you hope for your future again, and the tools to make sure you can spot and avoid men who'll behave like this.
Www.freedomprogramme.co.uk
You can do the online course or go to a group and get support and solidarity from other women. If you go to a group nobody will ask you to share your experiences unless you want to, you don't have to stand up and speak in front of everyone, you can just listen. But it's information that will give you back power over your life.
I'm really sorry this has happened to you. Be kind to yourself. It will get better.