Any Advice Ladies ?? Trust Issues

Hey there beautiful ladies I have a problem ok Soo long story short a few weeks ago I caught my boyfriend texting his ex girlfriend of 3years he said he was just trying to help her get over him but when I asked the girl she told me that they talked about getting back together one day that he said he didn’t have a girlfriend he doesn’t have time for one etc... You guys get the picture right so ya I confronted him about it and yes he deny it he even called his ex and asked her why did she lie they never talked about getting back together yadda yadda yadda i gave him a second chance because I do love him but ever since then I haven’t been able to trust him completely and I’ve been paranoid ever since I mean I have his password to everything but since I am not with him every second so idk if he texts other girls and deletes them when I come idk I’m just lost how do I start to trust him again or should I ever even trust him again ??? Idk what to do