Me 'M20' and my partner 'F22' been together for 3 years, 3 years that we’ve had these up and downs a lot of beautiful moments but like every relationship some down ones, couple months ago she said ive been lacking in giving her some kind of love or attention, so she tried breaking up with me saying she needed space and time to know what to do and requested a "break", i didnt wanted to and told her ill work on what needs to be worked on, she agreed and were still telling me we were together as she was going out to clubs going to see this guy that they had a past with each other, they were acting like a couple for about a month then they stopped talking and she said how sorry she was and all she wanted was me, i accepted her apology and believed her
Then her friend went through a divorce so she wanted to help her out "change her mind" and be there for her which i had no problem with, she was lying to me of places they were going, of people they were seeing, they went to see guys multiple times and she kissed multiple guys saying that she was "pretending" and it was just so her friend can get the other guy, ( which i found ridiculous), she kept on telling me how she loved me and she’ll stop she loves me im the only one she will ever love this and that, and because i love her and ive spend 4 years with her i want a believe her but i have 0 trust in her anymore she isnt really trying to build that trust back honnestly, i dont know how to talk to her telling her i want a check her phone (because right now we are working our way back together, a fresh start) but i wont be able since i dont trust her and i dont have her passwords or social media accounts anymore i just need help with how to deal with this situation and what do you guys think of all that? any advice would be appreciated
TL;DR! 3 years relationship went sideways after i lacked some emotional stuff, she looked for it with someone else, while telling me we were good and together, i forgave her and she redid it multiples times what do i do?