[fallen11]

if you cant trust your gf
Better off finding another gf instead
Whether she cheats or not
This trust issue will continue to screw your heart and mind, hurting your own mental health.
If you are in a serious relationship, there has to be certain level of trust.
If you're just in it for the sex, then you also wont bother too much if she cheats or not as long as you continue to get the sex.
If she cheats eventually, just get another gf.
Take the chance to up beef your self confidence instead of trying to find ways to hack into her phone.

For me, i always give the 1st chance. I will not have suspicions about her. Call it naive if you will.
But once that trust is broken. No 2nd chance will be offered. Dont look back.
Even if i were to keep her after the trust is broken once, it'll only be for the sex when i want it. At the same time hunt around for someone better.
Take control of your life, dont let others control yours.