How is it being weak if you stay?

Something I never understood is how some girls can turn on others who has had a crises of some kind in their relationships, thought of leaving or perhaps left, but then returned to their partner as he admit where he went wrong, apologize, work on himself to never subject her to it again. Is it not up to the girl herself to make that call? Is she not equally strong, if not stronger for staying? Is not forgiving someone strenght? Is it only a weakness?

I've been by my friends side no matter what they've been through or what they're decision been. I was by my moms when she reflected on staying or not with my dad. I told her I only wanted her to be happy and I would not blame her for leaving or for staying, it was between the two.

I've seen some girls who leave that they push down the next chance they get their new partner to reinforce their boundaries, why they left or was left by their ex over this issue, and it is too much so, as if they are ready to go out at war, as if the new one is the ex, they're not equals. They push them down like little boys in general and then one day they wonder why they left...

They only see themselves as the strong women and if some woman they told to leave won't in the end, they then think she's weak and she's not part of the "strong womans club"? What bs is that? If the partner admit he's wrong and change and she's giving him a last chance how come she gets to look bad? To me no matter it isn't the woman in this scenario that looks bad, it's her partner. Why punish her?

I don't buy that these "strong" women, I don't think they have healed themselves and they use anger as their fuel. If you're not with them you're against them. They couldn't recruit you. They're not good sisters or friends, in my opinion.

Updates
3 mo
As a friend I've always stood by my friends side no matter what they've been through with their partners. The experiences I've had of someone being in a emotionally abusive relationship is that I never myself played the ridiculous "strong woman card' but was simply there, not turning my back, not judging, and I knew when her moment came she knew I would help her (and I did) but that was with someone she still had hope was changing but wasn't.
Updates
3 mo
in my opinion I never viewed myself as strong or stronger than any other woman when leaving a relationship. It was about having lost hope. I've never heard the phrase that other men go around saying they are strong men or other men saying it about them. The women I am referring to were in reality not healed and sadly became out of their own fear Bosses over everything meaning it was no longer about fear of one boundary being crossed. Their fear stuck, infected everything.
How is it being weak if you stay?
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