I am on and off of my computer throughout the day and generally have Photoshop open through Lightroom. When I walk away for a bit and my computer locks itself or sleeps, it automatically shuts Lightroom down, losing my connections to Photoshop and pictures I'd been working on. It's very frustrating. I've looked in menus etc.
Also, there is no way to stop it from closing. Just says "back up?" or skip.