Cheating GIRL FRIEND

I am M(23) and My girlfriend (F22) cheated on me with her ex. We had a small argument about how much i do for her and if i start telling what all i did for her it will be a lot. and she made it like I am a bad person as i say what i do to her. She is financially very weak so i take care of everything in her life. Clothes , food(Gave a zomato account with my simpl wallet so one click food for her) , shoes , iphone, airpods, her sisters needs(headphones, clothes etc.) , washing machine for her house you name it it was on me.

So one saturday she meets her ex and told me she is just taking a nap and the same evening fights with me saying i dont let her sleep when i called her at like 8pm and she took a nap at like 3pm. Naturally i was apologetic but she didnt budge.She blocked me from all places and i was confused and crying everyday to get her back. All this while she was cheating on me . She was in touch with her ex and even slept with him , they abused me in front of my friends , my brother and sister too. She even got goons who threatened me if i tried contacting her. She went on vacations with that guy and all this while she is saying i am giving you a chance that you improve, be a better person but she was just cheating on me. I got to know all this when the guy showed me pictures of chats and calls and to be honest it all was just too much for me.We had plans for getting married. My parents knew , they were kind of hesitant but were. helpless in front of my stubbornness. Her family really liked me. I was really angry .2 months later after this fight I am crying contemplating suicide , begging her to come back being sorry for saying what i said. Mentally tortured. By luck her dad called me for the first time to discuss marriage and i just told him everything. Her dad put her in her home for a week and did not allow her to go out. When the other guy got to know about this , rather than supporting her he left her.

She made up a story in front of her dad that i am a bad guy and she did'nt do anything wrong and hid everything. I had proofs of her cheating, the booze., the sex, the vacations but i decided not to share with her dad. Now i am mentally hurt and I want revenge. So i blocked her phone(It was paid by me) and put it on lost mode.

She even threatens to do police action on me. after the lost mode thing. Idk what is happening. I will ask her to give it back? Am i the asshole here? What should i do nowP.S: . And the other guy is of a different religion, so they end up marrying is impossible. My gf was in a relationship with this guy in clg for around 3 years and then broke it off coz there was no future for them. Then she came in a relationship with me. She used to say that he was physically abusive used to cheat on her. But still she went back to him. And all this while she gave me false hopes that i am giving you a chance to improve then we can marry as marriage with me was favourable due to a number of factors( same religion, good career , good family background). And in 2 months i cried had sleepless nights begged her to come back. She didnt care but laughed at me and made fun of me in front of my friends and my brother and sister.