Got cheated on many times by the same girl

Hello everyone im “23M” and my ex is a “22F” . we was together for about 5 years. A short summary of what happened is a few days ago i found out i got cheated on multiple times throughout this relationship, there were a few signs here and there which i did ignore my gut and she would reassure me nothing has happened.

It was mostly flirting and kissing other guys, the main one that has really hurt was she had sex multiple times with a guy , and it was after one week of knowing him and told him she was a virgin, they were basically in a relationship commited to eachother, i found out she would lie to her little brother to this guy so he doesnt mention me around him , me and her seemed to be all good at the time this was going on apart from when she found out she was pregnant with his baby i found out, she become distant to me and we had arguments, at the time she told me its just her period issues etc. im not sure whether she had an abortion or miscarriage.

What has really hurt me is after knowing all of this she has denied everything and even threatened to call the police on me because im apparently crazy and trying to ruin her life with lies. i told her i will tell my family about this and she had tried to ring me i didnt answer, i havent heard or spoke to her since she has not reached out to apologise or own up to the truth. I feel empty and not good enough, constantly thinking about what i did wrong for this to happen to me, what they did that she liked so much to do this to me, i thought me and her had an unbreakable bond we was so close , its hard to know the person you shared so much with and was vulnerable around done this to you, and there isnt an ounce of respect for me to even come clean with the truth, if i had never of reached out to this guy i wouldnt never of known and she wouldve kept it from me forever , however long we wouldve stayed together.

Why didnt she just leave me alone if she wanted something else? she constantly was at my throat about thinking i was cheating, she could be insecure so id reassure her. If anyone hear knows the answer to why she kept me around and acted so inlove with me but done this behind my back it would be appreciated because right now my head is so messed up , it still hasnt sunk in because i just didnt expect it from her, i feel so betrayed and probably wont trust another woman again.