<human>: Can you give me the gist of the text in a nutshell?

Hi there, I have a feeling this post will be filled with grammatical mistakes and I'm sorry in advance.  
   
Today I figured out my girlfriend's instagram password, the reason for me even trying to figure it out was because we've had a past experience of her getting a little to close with another guy on insta.  

The first thing I saw when I looked in her dm's was some messages from a guy she told me not to worry about. It was about the last time we had sex, I couldn't see any previous conversations or how this conversation had started because she deletes her messages because she's afraid her mom will go through her phone.  
The conversation started with her saying 'this tuesday' and he asked what positions and she replied with the positions we'd done, he asked her how many times she orgasm'd and she told him how many. The guy then said I could do better and she said "No you couldn't" and then he sent the final message which was 'alg ur life'.  
I don't know what to make of this, I don't know why she's comfortable telling random people that want to have sex with her about OUR sex and it seems like a huge break of trust. I don't know if I should confront her about it now or sit on it for a while and see if they talk more. I have snooped on her phone before and found stuff similar to this and she changed all her pw's, so confrontation with her would be ugly.  
I really really love this girl and the last thing I want to do is break up with her.
<bot>: girlfriend talks to guys on insta that are looking to hookup with her about our sex life. I don't know what to do about it.