Trust Broken - Another Girl Involved, HELP!?

This is my first post and I’m not sure where to start so I guess I will start from the very beginning. I met this guy on a dating app and we were straight out just texting everyday for a few months and finally met, granted he was only an hour away from me. Now we have been seeing eachother for a month or two and I really like/liked him. He has been good to me and so forth, but we haven’t had sex. We talked about it, but he kept changing his mind. We aren’t officially dating either because he has never asked me, and it’s been brought up before, so I thought “okay maybe he’s really just that shy and needs time.” Up until last night, I get a text from my brother’s ex and my close friend who I can consider an older sister. She tells me that a guy named *the guy I’m seeing* added her on Facebook dating and liked her; they matched. She didn’t know I was seeing him until I said that and we got into heat with him. He was calling her beautiful and saying how he’s been waiting for someone like her to enter his life and all of this other shit. Of course I would find out, are guys really this naive? I confronted him about it and at first he denied it all, saying he’s not on a dating app or anything, until I kept ranting and swearing at him, then he finally said “fine I texted her, but I only want you.” What the hell? So you lie and then lie on top of that lie again. Later on after texting back and forth, he gives me the pity party trying to make me feel bad for his actions. He didn’t even apologize until I pointed it out and it was forced from him: “Fine I’m fucking sorry I did that.” And then he continued to say he was sorry for himself that he did it. I was rude as hell because I’ve been hurt like this before, but after deleting his number, today at work right now, I just received 10 messages from HIS SISTER saying that he’s sad, crying, wants to die, and that he’s just miserable, and I just don’t know what to do. Help?