I (29F) discovered my boyfriend (31M) invited our mutual friend over while drunk, and now I’m questioning everything.

My boyfriend and I have been together for just under three years, and we live together.
A few days ago, I discovered messages from my boyfriend to one of our mutual friends that were sent while he was intoxicated. In the messages, he was asking her to come over. He insists nothing happened, but I honestly don’t know what to believe.
I confronted him last night, but it was very late, and we agreed to wait until he got off work today to have a proper conversation.
This morning, I noticed that our mutual friend’s contact had been deleted from my phone. I was able to recover it, but now my mind is racing. I don’t know if he deleted it while I was asleep because he was worried I would contact her, if it was somehow accidental, or if it’s completely unrelated. I realize I don’t have proof that he deleted it, but it’s adding to my anxiety.
Right now, I’m trying to separate what I know from what I’m assuming. I know he invited her over while he was drinking. I don’t know whether anything happened after that or whether the missing contact means anything at all.
I don’t want to go into tonight’s conversation angry and accusatory if there’s another explanation, but I also don’t want to ignore behaviors that could be signs of dishonesty.
For those who have been in a similar situation, how would you approach this conversation to get honest answers while also protecting your own emotional well-being? What questions would you ask, and at what point—if any—would you reach out to the mutual friend for clarification?