You bring up a very interesting point. If you have ever known a BPD lunatic like Chantal, you realize that in their mind they live in their own reality. Anything in the past that they did that was shitty, no problem --- rewrite history.
They then tell themselves the new updated "history" and then start believing it.
I think it also speaks volumes for the fantasy world people like Chantal live in and their sheltered real world.
You hear people like her all the time talking about how they'd have tackled a terrorist if their plane was hijacked or how they would spring into action during a school shooting, or even just how they'd punch someone who got up in their face when in reality they've never faced any kind of actual conflict, crisis or confrontation.
A lot of us (at least in the western world) grow up on media that places us (or our in game/movie/show analog) in a position of power and romance, depicting protagonists (with flaws like ours!) as powerhouses of vengeance, justice and/or romance and it takes a lot of self awareness for some people to step outside that and say "Actual I'm just John Smith who works at Big Office and I'd piss myself and cry if someone showed up with a gun and started shouting."
Obviously this doesn't apply to everyone, but to people like me and
definitely Chantal who have never been in a combat situation, acknowledging limited experience and capabilities at least means I'm not going to beat my chest in public and brag about how I'd protect my boyfriend and our home while under fire. I'm not a teenager who feels invincible anymore, I'm an adult who has been in fights, who has pushed their limits, who knows pain and loss and fear and has enough responsibilities to know that if I throw myself away pretending to be a hero, it's the people who depend on me who will suffer, or if I survive then how long and painful the road to recovery would be.
Chantal has never faced a challenge, she has no idea what her limits are because she's never gone far enough to actually hit them. She gives up and falls to pieces the very second something is even mildly uncomfortable or slightly challenging. She's also never cared about anyone but herself to know true loss*. She is at her very core a spoiled, sheltered teenager who will always be bailed out or be able to tuck herself away until it all blows over.
Because she doesn't know her limits, doesn't know what it takes to fail or succeed and doesn't know true wins or losses, she can still fantasize like we all did as invincible teens. She's spent 40 years throwing pebbles and telling everyone she could pitch a boulder because she's never actually tried so she doesn't know the difference in effort, they're just both rocks to her.
I'm going to put down the beer and hope some of that was coherent.
*In my opinion. All of her "mourning" has been because of what she's lost as a result. She didn't care about her gram, she cared her gram wasn't there to give her shit and spoil her. She didn't care about losing Nadar to Deedee, she cared about losing the attention and validation she'd bought.