Heartbroken

I am truly going through it. I’m feeling it all, everyday. My boyfriend and I were so close. We have been together over a year. I struggle with confidence, more so jealousy. i am constantly comparing myself to other people and feel like i’m not worthy. he left me almost 48 hours ago. It wasn’t a nasty breakup, I thought it was genuine. Right after, he starts following random girls. He stayed out at the bar until 3 am. Lastnight- he went to the strip club, until it closed. After that, he went somewhere else until 5 am. My heart is completely shattered. I can’t eat, i feel nauseous all day long, my heart races, and the thought of him and what he’s doing makes me stomach churn. i gave him all i had. i gave him 100% everyday. i chose him every single day. i did all the things good girlfriends should do- and that still wasn’t enough. if anyone has some advice, it would be so appreciated. i am hurting now more than ever. i’ve never felt more alone, defeated, and unworthy. How has he moved on so quickly?