<human>: Can you provide a brief overview of the text?

I have been with this girl for 6 months and we both love each other. 2-3 months into our relationship i found out she was hiding a guy that she hooked up with in her phone under a different name and hiding the fact she talked to him. After i found that out she apologized and i decided to give her a second chance. 

My girlfriend is going out tomorrow night with her girlfriend and a guy friend which i have no problem with. Today i received a text message saying my girlfriend is going to a house party with her friends mentioned above and is inviting her ex boyfriend of 4 years before me. Shortly after they ended things we started to date (rebound?). We both love eachother and have already been on 1 vacation together and have one next week..(oh boy) 

She thinks that i snooped through her phone and found this information out but i truthfully did not. She thinks this because that's how i found out about the first lie. I know it was wrong to do and i shouldn't have done it but i can't take back what i did. It turns out this text i got today is true. She started to flip out and said that i have lied in this relationship when i haven't and is trying to turn it around at me. She intitially denied everything but then said "yea, well you've lied before too" I really love this girl but i'm drained of dealing with this bullshit and sick of being lied to. She says she hasn't talked to her ex which i believe tbh and hasn't cheated on me because we sleep with eachother everynight the past few months. Is this a deal breaker?

Sorry for the grammatical errors, my phone keyboard isn't very good.
<bot>: Girlfriend going out with a few friends tomorrow night, wasn't invited because not 21. Turns out it's a house party at someone's house that she doesn't know and is inviting her ex boyfriend.