Deleting messages

Whenever my phone dies I use my husband’s phone to text/call someone. Yesterday I was on the phone with my mom and it went dead so I asked to use his phone to text her and let her know that it died. When I went to text her I saw a message from someone that said “damn you just left me on read” and I clicked on it. The first message was something like “because it pissed me off” so I knew he deleted their messages and he had her notifications silenced. I didn’t let him know that I saw it because I wanted to see what else they’d talk about. Once he went to sleep I looked in his phone and he deleted their conversation. He’s acting normal so I didn’t even question that he’d be cheating but now I know he’s being sneaky because he has other female friends and he has all of their text messages on his phone.