I think Lois and Joe's daughter still exists in that reality. Lois and Clark thought it was strange, but they also said "it seems this version of us are happy being married to Joe and Lana." Now the Lois who is traveling through time doesn't really care about her, because she isn't HER daughter and she doesn't know the little girl. But, Lois and Clark didn't DO anything to that reality other than go back and change Latislan so they would get married (and hence, create a NEW REALITY).
As far as Lois and Clark trying to change the past, they're not doing it so everything will end up perfect for them in every reality. As stated, they thought the reality where Lois was married to Joe and Lana was married to Clark was strange, but they admitted that version of themselves seemed happy. They were happy the version that got divorced and decided to try dating seemed to be working things out. Furthermore, there was the reality where Lois died trying to get to the cabin. THAT certainly didn't end well.
All Lois and Clark want is to get THEIR OWN LIVES BACK. THEY are not happy being married to Lana and engaged to Joe. (see beginning of 17 and 18 when Tempus first fixed it the timeline.) And THEY are not happy unless both their sons are with them. - Note WITH them, not with whatever version of Lois and Clark they come arcoss.
Now the question is, when all is said and done, are they going to create a new reality with a new version of them when everything is fixed the way they want it? Because, as I said, they create new realities everytime the change time. So how does this get them back to THEIR REALITY? Will it really become their reality when time catches up like their hoping? Or is the only way to recreate the car accident?
