Jimmy doesn't realize that lying and keeping a secret had a major impact on the Community. Kelly went to jail for a hot minute and The Taxpayers had to pay for what they did. Even when they were all alive they were the Town Pariahs. Can you imagine how lonely they must have been. No Friends no happily ever after. The only positive thing was Jimmy is "happier". If Matthew, Tom or Carl had lived they would have made Jimmy's life unbearable.
Jimmy's biggest problem is that as The Middle Brother he probably felt he had to be the "Mediator" between Matthew & Carl. He loves Matthew because he knows that Matthew is a Better Businessman and can handle "Issues" with folks better than he can, he loves Carl because he's his Baby Brother who may have looked up to him as Children. It kind of parallels The Episode of The Brady Bunch where Peter breaks the Vase and allows his Five Brothers & Sisters to be punished. His Parents know he's guilty as sin and they play him on it to the point that he breaks down sings like a canary and owns up to what he did. Sadly enough there's alot of Family Members who "Mess Up" and they always get rescued or forgiven yet as time goes on Family get sick of their behavior.
Matt could have said "You were always the Apple of our Father's Eye." Carl could have said "He didn't want me to be happy with Chas because of what happened with Charity, he felt that no Dingle could be trusted, but we were the untrustworthy ones, we indirectly caused the Death of Dawn Hope, then we were angry at Bob because we thought he killed Dad, and to think he was lucky that Dawn forgave him for abandoning her but we treated Scarlett Mary like dirt, so many people hated Dad for what he did to them but who kills him, me."
I was disappointed I thought there would have been a twist I thought Tom would have just died of a heart attack and that’s what made him fall out the window
Emmerdale - Tom King's Murderer is Revealed (2007)