

We are just asking old questions here. The printing press, novels, and pamphlets were the end of truth! We struggled, many people died, but life moved on. Then newspapers, more death, radio, world wars. Television, photoshop, the internet - fewer deaths in between but still. And life moved on.
Every new medium brought a phase of uncertainty (and possible carnage). That’s where we are right now. Every time we think “this is the worst EVER.” Until the next thing comes around. We will figure out the slop tsunami as well. I think fewer people will die than during the reformation.
Some people will successfully bend truth to generated video or whatever. But in the end, most will not succeed. Because we get wiser at spotting the bullshit. Q Anon showed us the learning isn’t a linear development; it follows more of a two steps forward, one step back pattern.
Kids are probably old enough to get it. I would just think that you will be loading a shotgun that’s going to shoot you in the face down the line. Either the ladies will get in each other’s hair or, worse, they’ll team up against you. I think your girlfriend is either insane or not entirely honest when she says she would be fine with your arrangement. I would sooner suggest you look for a place closeby. I’m guessing the 15yo is eye rolling you hard and the 13yo will soon not care about you either. You’ve carried them through the divorce rough spot with your unique living arrangement. Take a bow and let it go. Provide a better environment for your new relationship.