How do you handle mildly suspicious behavior?

From your partner, I mean. The kind of things that are subtle and could be easily denied or explained away.

Do you file it away? Try to get in touch with your intuition? Write it off and wait for more obvious evidence? Mention it to your partner?

I find that really small, strange things happen and because I’m insecure and afraid of infidelity, I feel like I’m on high alert.

Things like:

The sun visor in hubby’s passenger seat down and he says he never takes anyone to lunch (even guy friends).

Lunch expenses that seem like it was probably for two people based on the amount.

An employee calling at 9:30 that he doesn’t answer. This employee never calls and he typically will answer work calls.

A gift from this same employee that he wanted to toss but then I found lying around and he said he didn’t know why he kept it.

Working super late regularly, but enough time where he answers the phone, I’ve been in his office with him, or I hear him answer calls from his boss after hours.

He has lied about stupid things before but says he would never cheat on me because it’s so disrespectful. But he has been disrespectful and dishonest before, so it’s hard to reconcile if he actually values integrity.

We’re married and have kids together. I’m looking for how others deal with this stuff, not a “if you don’t trust him, don’t be together” feedback. Obviously, relationships are too complex for such simple direction.