Pink did everything she could to stop the invasion before she resorted to starting the rebellion (Pearl says so herself, being present for countless meetings between Pink and the other Diamonds where she begs them to end it, in the episode "Now We're Only Falling Apart")
And from the very start (as seen in the episode "Jungle Moon") the ONLY reason Pink wanted a colony was to gain respect from the other diamonds by copying them ("I want to command a drop ship!" "I want a colony!" "It's not fair! I want...my own army! I want my own planet! I'm just as important as you!").
In that episode she clearly didn't know what Yellow Diamond was doing (she literally starts the conversation by asking what Yellow is doing, and tries to participate), nor what it meant. All she knew was that Yellow was respected for doing something important and Pink wanted to be respected by doing the important thing too--all the while Yellow kept scolding and dismissing her.
Pink Diamond was neglected and abused by the other diamonds (Pink was constantly locked alone in the tower on homeworld for ages at a time, for every little thing, even as harmless as what Steven did by wanting to dance at her own ball, as seen in the episode "Escapism"), and was convinced that the only way to get them to treat her well was to do what they were doing
And when they finally gave her Earth, she was so desperate to be respected by them that she left her playmate Spinel behind to prove that she was 'mature' now and done playing games (you see how Yellow was always watching her to make sure she wasn't goofing off in the episode "Together Alone" so you can understand why Pink wouldn't want to goof off with Spinel anymore).
(Abandoning Spinel is 2/3 bad things that is valid to hate Pink for, but you have to understand that being left behind was normal for the other diamonds to do to Pink, which was also referenced in the lyrics to the song "Familiar:" "they love her but they're leaving her behind." And as Rebecca Sugar said herself, Rose/Pink didn't think Spinel valued her enough to actually wait there for her)
(The 3/3 valid reason to hate Pink is how she handled Bismuth, especially since she didn't free Bismuth after the war was over. There's no defense for keeping her bubbled after the war, I'll give you that)
Pink was bored out of her mind with overseeing the colony because she never actually wanted the colony in the first place, she only wanted to prove herself to the other diamonds.
And when Pink did see the consequences of her colony hurting Earth, she pleaded with Blue Diamond to end the invasion (episode "Can't Go Back" direct quote from Blue scolding her, "But this is what you wanted. You begged us for a colony of your own, and now all you want to do is be rid of it."). Blue didn't even let Pink speak. She shut Pink down just like she and the other diamonds ALWAYS had and kept the colony going.
And we all saw how White Diamond doesn't let anyone get a word in either (in the episode "Legs from Here to Homeworld"). And how White had refused to give her a colony just like the others (explained in the Steven Universe Future episode "Volleyball").
(Cracking Pink Pearl's face was 1/3 valid reasons not to like Pink, but Pink Pearl says herself in that same episode that it was accident caused by Pink Diamond shouting about White, and afterward Pink stopped throwing tantrums to prevent from harming anyone else)
That's why Pink had to become Rose and start the rebellion: so the other diamonds would actually be forced to hear what she had to say, even if it wasn't herself saying it (again said in the episode "Now We're Only Falling Apart").
Y'all are literally hating on an abuse victim standing up for herself (AND others who were abused by the same system, like the "off color" gems and the Crystal Gems, who ALL would have been shattered just for either existing, or for loving each other/fusing as shown in the episode "Together Alone", or for wanting to do things that they weren't assigned to do, as seen in the episode "Your Mother and Mine").
The war wasn't just "Pink fought herself." The war was finally standing up to a system that abused, killed, and oppressed its own constituents, and that also killed life on countless other planets.
Y'all also want to blame Pink for the gems on Earth being corrupted because of the war, but 1) the other three diamonds were the ones that corrupted them (their hands depicted emitting the corruption blast seen in the episode "Your Mother and Mine") including Homeworld gems who didn't evacuate in time (such as Centipeetle, can't remember her name, in the episode "Monster Reunion"), and 2) the other three diamonds were the ones who made the Cluster (as Peridot says in the episode "When it Rains") by gathering the shards of the shattered gems to use in horrifying fusion experiments to destroy Earth even after they lost the war (as stated in episode "Keeping it Together" also in which Garnet plainly says Rose couldn't have known about it).
Pink/Rose is NOT a bad person and I will die on this hill.
Before you say she's a bad mother, I pointed out how senseless that accusation is in my other post:
https://www.tumblr.com/butterflymasking/753213325116145664/apparently-steven-universe-has-been-getting?source=share