Rocket Raccoons strongest soldier

We know that the feud between them started when Dutch killed Colm's brother. Colm murdered Dutch's lover Annabelle in retaliation, and things spiraled into the decade-long war we see during the game.

According to newspaper clippings, Colm and his brother were close. They rode together for years, probably since childhood, all the way up until ~1889. By that point they'd have been in their thirties or forties (assuming they were close in age). That's decades side by side.

And here's the important part: the O'Driscoll Boys as we know them only came into existence after Colm's brother was killed.

Colm's brother dies → he kills Annabelle and founds the gang → the feud with Dutch explodes

That doesn't sound like a guy who "never liked" his brother much. That sounds like a guy whose entire trajectory changed because of that death.

ARTICLE 1 (from Blackwater Ledger No. 69):

For nearly ten years, citizens of numerous Western states have fallen victim to the savagery of Colm O'Driscoll and his gang of outlaws. They have robbed coaches, battered women and men alike, murdered, tortured, and committed sundry unmentionable atrocities. His wild, hot-headed and impulsive ways are the stuff of outlaw legend.

ARTICLE 2 (from Blackwater Ledger No. 70):

Since the death of his outlaw brother a decade prior, Colm O'Driscoll has run with both Irish and American hoodlums willing to die for a few dollars and some whisky.

When Dutch offers his fake, forced apology during that meeting, Colm shrugs it off. It sounds dismissive and that's the whole point. It’s a power play.

And that parley? That wasn't Dutch's idea, it was Colm's. He pitched it as a chance to bury the hatchet when it was actually a trap to lure and capture Arthur. Colm knew it but Dutch didn't. Which means every word Colm says at that meeting, including the "I never liked him much" line, is part of the performance.

Why I think Colm was lying (or at least bending the truth):

His answer undercuts Dutch's apology

Dutch is playing a psychological game with an apology he clearly doesn't mean. He's extending a fake olive branch, setting up a moral balance, and trying to pressure Colm into apologizing for killing Annabelle. Colm's answer flips the script. "You didn't hurt me so your apology is worthless". It also destabilizes Dutch by mocking his own loss: "I killed the woman you loved over a man I didn't even care about".

We also know Colm isn't just out to kill Dutch, he wants to humiliate him (and vice versa). He knows Dutch thrives on control, appearances and the belief that his gang is guided by higher principles. Dutch says "We're both men who've lost people, so we're equals here" and Colm replies "No, I didn't lose anything that mattered. You're the one who's soft and weak."

It protects Colm's image

No way is Colm about to admit grief in front of others, especially not Dutch. Vulnerability is weakness, and weakness gets you killed in their world. Even if he was gutted when his brother died, he's not going to show or acknowledge it, especially in front of his own men and his nemesis

The Annabelle problem

If Colm didn't care about his brother, why kill Annabelle in revenge? Why her, Dutch's lover, specifically. Not Hosea, Dutch's partner in crime. Not Arthur or John, his surrogate sons. Colm targeted the woman Dutch loved.

That choice feels personal. It's like Colm was saying "I can hurt you in the most intimate way possible". It also shows he wasn't afraid to escalate. He could've picked someone more "strategic" but he went straight for emotional damage. That tells us two things: (1) his brother's death meant something and (2) Colm is the kind of man who settles grief by making the other guy hurt harder

The feud itself proves he cared

If Colm truly "never liked" his brother, would he have sparked an all-out gang war over it? Would he have founded a whole outlaw empire following that death? I doubt it. His actions don't match his words

So was he lying?

I think so, at least partly. The best lies usually have a sliver of truth and maybe Colm and his brother did clash or butt heads - what siblings don't? But the "never liked him" act feels more like strategy than honesty.