Should I be suspicious??? UPDATE

This morning my husbands phone was going off and it was his buddy that he games with, so I was messaging his buddy (let’s say Jake) joking with him to fuck off because my husband was sleeping and I silenced the conversation so he could sleep and right under jakes conversation on fb messenger there was a conversation with a girl he went to school with and she stopped before I started attending that school (we’re high school sweet hearts).

Well, I didn’t read the messages. I didn’t even open the conversation, which was difficult because I felt like I should’ve, but I want to trust him so I held back.

10 minutes later he’s awake, and I tell him his Jake messaged him and I messaged him back. He says okay and he told jake it was me who messaged him, and he’s saying that it’s weird that Jake isn’t responding, and I told him I muted him so he could sleep. He asked me to unmute him so I did and I backed out of the conversation to notice that the conversation with the girl has been deleted. I don’t know what to do. I don’t know if it’s worth bringing up and causing an issue about, but why delete the convo? There must’ve been something to hide right? Or am I overreacting? What should I do now?

UPDATE: I talked to him. He said he doesn’t know why he deleted. He said he basically just didn’t want me questioning why he was talking to her. We have a rocky history so yes I’ve had a reason not to trust him before. I mostly believe him, it’s just odd to me. Thank you all for your input!