relationships

i’m 16, very young and i would love advice so my boyfriend has given me too many chances, i have flirted/texted other people(2 people) talked about missing my ex and things like that. i’ve left him heartbroken but he still wants to try but every time i think of it, it makes me sick to the stomach that i could even do those things, i lose my appetite, and i start to cry and my stomach starts to hurt. should we let go of each other ? or try to work it out ? i love him and ik people may thing you wouldn’t do those things if you love a person but i was stupid and made dumb mistakes and am willing to fix.