I am mid 50s and have always been overweight because I love eating too much.
I hear you.
It's really, really hard work re-programming our brains to regard food as fuel. Something that helps me is conspicuously posting in the kitchen a printed table from a nutritionist with portions and variety for the week's meals. This along with "fueling" five times a day (rather than the customary three) helps keep me focused on calibrating exercise and nutritional intake. I don't obsess over it and, in fact, I cheat on occasion (like adding peanut butter to my chocolate ice cream last night!) but when I'm working towards a fitness goal, it helps me calibrate overall intake and caloric burn.
One thing I struggle with is when I come off that goal (either because I accomplished it or something got in the way) I have trouble ratcheting down my portions. I keep sub-consciously thinking I'm going to get right back into high-intensity workouts. Like you, I'm in my 50s and know that my metabolism has slowed a lot and that sustained fueling for increased performance while on a decreased performance schedule can lead to, you know it, undesired weight gain.
One thing I have learned about LOB eating is to really, really exercise portion control. Nothing is worse than having a full stomach on a dive that interferes with ideal breathing. I absolutely hate that feeling and would rather be hungry.
Great news that you enjoy cycling. It's a great V02 maximizer. Hope you stay on trajectory where taking off that electric motor becomes a goal.