BF's wife rarely calls or texts when we're together. At 14 months into this, if she did, I'd have an issue for the simple reason that she and BF agreed to seeing other people outside their marriage, and to my mind, that gives them some obligation to remember those other people they want to have fun with are people, not toys for their amusement, people who have some rights to be respected, too.
I'd have a huge problem with being told we can't get together even for coffee, once every three months. Ultimately, of course, Bob is agreeing to this 'rule.'
I personally wouldn't continue seeing someone under these conditions.