There's not a lot of non-shit alternatives, that don't also sugarcoat stuff or recommend stuff that's not true, but it's the PC thing to say. It's hard to describe what I mean, clearly, lol, but I learned a ton from Todd Valentine (definitely PUA) and Corey Wayne (relationship/mindset-centric).
They both have pleeeeeenty of red flags, but I learned things from both of them that would've otherwise be lost to me or taken me way longer to find. If someone doesn't want to wade through shit, that's a-ok, but I trusted myself enough to be able to tell right from wrong and take the lessons that I felt were useful.
Anytime, bud. People ghost each other for a variety of different reasons during like the first 6 months of the dating process, sometimes even after that. It's just become an acceptable thing to do. There's different things you can try if you do get ghosted, but they're usually not worth doing especially if the girl ghosted you due to over-texting / neediness, whatever. I would definitely focus on staying on the app, working out, getting hobbies (do improv or something that'll get you out there), and just seeing what happens.
Before I started getting into reading/listening to coaching stuff, which I personally recommend, I was ghosted by a gorgeous girl who I literally had non-stop sex sessions with multiple times a week for like 3-4 weeks. Just disappeared. It happens and while you shouldn't blame yourself (or her, you don't know what she's going through), you should try to analyze if there was anything you could've done differently or examine how you were feeling while dating the girl (nervous, anxious, whatever). For me wanting to understand women and why I would get ghosted is what led me to check out all sorts of material, because having some sort of mentorship is better than none. Sometimes you get ghosted and you'll never know why, just keep living your best life and it'll all work out.