He cheated over 15 times

He cheated over fifteen times and I had no idea. I only knew he had cheated twice (physically) and stupid me decided I'd forgive him. somehow i found a way to convince myself it was something i was doing wrong that made him do that, something about myself. I forgave him recently as long as he promised to give me his snapchat and i'd give him mine and i found TONS of messages with all these girls and some i knew weren't saved. I'm only 16 and i lost my virginity to him, and now I feel worthless. We were only together for a little over 8 months. I honestly feel like I have nothing to give the next guy who may treat me so much better. I knew at the time maybe i shouldnt be doing it but sometimes it's just super unavoidable and I just feel so shitty about myself now.