I don't think he experienced guilt or remorse. He was too much of a narcissistic psychopath to feel sorry, and he wouldn't be able to "snap out of" psychopathy. We saw his illusions of grandeur on the police body cam and his casual, cocky demeanour again when he went camping with his family while Gabby lay abandoned in Wyoming. (May she rest in peace).
Assuming this monster did take his own life, I think it's because he was afraid of being caught and imprisoned. Narcissists fear being outsmarted. They feel so strongly they are innocent, they believe justice would be unfair and intolerable.
I blame Moab police and North Port Florida police for enabling Brian and letting him go free .... three times. They let him free once in Utah in contradiction of Domestic Violence law, they failed to let Gabby's mother report her missing when she first sought help, and they allowed Laundrie to escape from his parents' home after Gabby was reported missing. He was supposed to be under surveillance, or taken into protective custody for questioning. Those agencies are responsible for this miscarriage of justice, and for their sheer incompetence at protecting victims' rights.
Brian's ability to escape and commit suicide / die by misadventure deprives the Petito / Schmidt families of ever knowing the truth. It deprives them of justice. It also allows the Laundrie parents to go free without recourse for aiding and abetting a murderer.
There are psychopaths in this world, and that's nothing new. People have murdered since the beginning of time. The police are entrusted to protect citizens from violence, and to follow the law. They didn't.
They dropped the ball, as they did many times for me, and it makes me sick.
Systemic reform is necessary worldwide or else all the public education about domestic abuse is for nought.
Rest in peace Gabby.
https://gabbypetitofoundation.org/
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I never give you my number, I only give you my situation.
Beatles