It was clear that Lala couldn't stick around in NCIS: Origins considering Gibbs has never mentioend her before. We just didn't know what would happen to the character, but the NCIS: Origins season 1 finale seems to have explained it all.
Caution: This post contains SPOILERS for the NCIS: Origins season 1 finale.
Throughout the NCIS: Origins season 1 finale, Gibbs, Franks, and Lala had to cover their tracks as evidence came up that Pedro Hernadez was shot by a sniper. Of course, eyes were on Gibbs, and we know he did it. Yet, we also know that he gets away with it due to NCIS.
The question for many was whether Lala would keep quiet, or whether she would eventually betray Gibbs, leading to him having to fight his way out of trouble. She opted to stand by him, understanding why he did what he did, even if she didn't quite agree with it.
What happened to Lala at the end of the NCIS: Origins season 1 finale
Lala was able to help save Gibbs despite his intention of turning himself in. As she raced to tell him what had happened, a girl and a dog ran out into the middle of the road, and the girl ducked as Lala swerved, hitting a car and flipping her own Jeep over. She crashed on the top of the, and it looks like she has died in the accident.
Now, co-showrunner David J. North wouldn't confirm with TVLine if she is dead or not, but it seems likely. Lala isn't mentioned at all in NCIS, and Gibbs says in the episode that he realized he loved her when it was too late.
There are still discussions about NCIS: Origins season 2 happening. We may need to wait to find out until then if Lala is alive or not, as there's been no official announcement that anyone in the cast is leaving. Maybe we could see her alive but need to rehabilitate somewhere, and that takes her out and eventually leads to her deciding to go a different way.

Gibbs met his second wife in NCIS: Origins
The end of the NCIS: Origins season 1 finale also saw Gibbs meet Diane Sterling, who is an important character in Gibbs's life. She is his second wife, the one who goes on to marry Tobias Fornell and is the mother of Emily Fornell.
Diane commented on Gibbs's eyes in the finale, and it's clear that there is more to come from this relationship. We have canon to tell us that, and we're going to find out more as the second season happens. Or at least, we should.
Something we do know is that Gibbs married Diane to get over Shannon, and while she loved him, she knew she couldn't compete with the ghost of his late wife. They will divorce, and maybe we'll get to see the divorce trial, which saw Diane "clear him out" as he told Ducky in NCIS.
There is time for the story, as the series has been renewed for a second season, and it will arrive in the fall.
NCIS: Origins is availble to stream on Paramount+.
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