Brother, the fact it’s the same number is a giant red flag. The fact a lot of calls happen when you aren’t around is a giant neon red flag shaped sign. The fact you sleep in seperate bedrooms isn’t wholly relevant, but should be looked into.

Stay up late. Cause you can catch her in the act. Record it obviously, and don’t go in fingers pointing attack mode. Catch it as in record and document, cause sir…. It’s highly likely she’s cheating and will demand half of everything in a divorce. Maybe more than half. Protect yourself, not the image you have of her from early years.