Snooping around on my husband's phone.

So this morning my husband received a text from his bestfriend.. I open the message and got curious to keep reading their convos... I came to a message of my husband asking his bf to send him a phone number of this girl from my husband's job. ((a girl we hooked his bf up with ))..... So I'm thinking why the hell does he want her number for? about 2 months ago I was washing his work jeans and found a piece of paper in his pocket with a phone number on it, I dial the number on my phone and I come to find out it's my husband's coworker (same girl ) . I called him pissed off and asked why he had her number in his pocket and he said she gave it to him. And he didn't know why. So basically denied anything and everything... So what do you'll think is going on????