AITAH for lying to my ex-boyfriend and telling him I have liver failure so he would leave me alone?

I know lying about something like this is wrong and insensitive, but please hear me out. I (16 FTM) was in a long-distance situationship with my ex (19 M). He found me through Instagram and was very intense and affectionate from the start, which I later realized was love bombing. A few months in, I visited him for a week. During that visit, he crossed some serious boundaries one being him trying to have sexual intercourse with me while I was asleep, which made me feel very uncomfortable and unsafe to say the least. After that, I started noticing red flags I had previously ignored, and I also found out he had been cheating on me. When I returned home, he ended things but wanted to stay friends. I agreed at first because I was emotionally dependent and didn't want to lose him completely. Not long after, he started seeing the person he had previously told me not to worry about and continued contacting me telling me sexual stuff him and his new partner did, even after l asked for space. I eventually blocked him. He then began messaging me on other platforms asking why I blocked him. Based on past experiences with him, I didn't think asking him to leave me alone would work, and I was just completely exhausted and done with that situation. I lied and told him I had liver failure and was going to die, and that I needed to focus on myself, hoping it would make him stop contacting me. I know lying like that wasn't the right thing to do, and I'm not proud of it, but at the time it felt like the only way to get him out of my life. So, AITAH?