Full disclosure, I've submitted over 30 apps across two cycles and about 20+ of them were all immediate post-app rejections/post online test rejections. I can't even count the number of days I've stayed home in bed upset over a rejection for an app I drafted 5/6 versions of, and the number of breakdowns I've had with friends and family over being "not good enough".
The more app cycles you do the better you get at writing them and the more your confidence builds at ACs. If you've already made it to one AC you definitely have what it takes to get past the app stage. I know it's easy for me to say now, but believe in yourself and keep trying! All you need is one vac and one TC, and it will happen!!
Just to add to the above, I've had around 40ish rejections over the two cycles I've done apps in, and failed 4/7 assessment centers. Before my TC interview with Links on a Thursday, I was riding a streak of 2 consecutive AC failures (Tuesday and Friday before that Thursday).
A lot of us, myself included, do not really post how often we get PFOs. But hey it's part of the process and pretty much every trainee/associate I've spoken to has had a crap ton of rejected apps (there are maybe one or two exceptions).
It's depressing sometimes, (I was very anxious as an international student going into my final year without a TC) but you'll become stronger as a result of it.
Your stories are inspiring and reassuring, thank you for sharing