Can men have female friends?
I do, and always have.
I found it very helpful to introduce my female friends, to my then g/f. She KNOWS THEM ALL PERSONALLY.
They are friends also, so there is no mistrust or suspicions at all. Over the years she has introduced me to her male friends,
we get along great. We always invite each other to events, or parties with our friends, sometimes we go together, sometimes we don't.
The bottom line is to know his friends, and keep an open mind. Another thing is always know where your partner spends time. (Even my kids always know where I'm at).
Don't assume without facts, but his reluctance has you questioning his actions, that's what you confront, his lack of reassurance to you, and his being forthright with what's going on.
Jealousy, or insecurity, will ruin everything.
Is that why you read his texts??