Abbusive

I've been with my boyfriend for a while now, the past month maybe longer he's been abbusive when he gets mad.. Last night he left at 1am, to go talk to his "dad" but I wasn't allowed to come, then when he gets home he was messaging a girl and I caught him, he changed his wallpaper from us, to just him, and I messaged him while he was gone, but he turned his phone off. Whenever I confronted him about it, he lied and said it wasn't a girl but I know it was, I read the phone. After me accusing him, he punched me multiple times and choked me. This is the first time it's been this bad, he never punched me until last night. But he has choked me to the point of vommiting. I can't find the courage to leave because I love him, please someone give me advice so I have the strength to move on and better myself before he seriously hurts me or kills me. I have bruises all over me and marks all over my neck.. advice, anyone? Please.