changing lifetime wants

Just wait the next day and see if it goes away. There might be a cheat about changing it but none that I am aware of.

LOL, that's funny. There is a cheat.
Open the cheat box. Ctrl + Shift + C
Type boolProp testingCheatsEnabled true
Shift + click the sim, click the spawn option
Find the mod sim option and click it
A baby will appear next to the sim you want to modify.
Click it and modify your sim as needed.

Good Luck

Well if you use the aspiration changer in the apsiration rewards, if you select a different aspiration, the lifetime want is sure to change. I know thats what got you the weird lifetime want but just make sure your aspiration is above gold (u can easily ensure this by using the boolprop cheats, shift clicking on a person, then click set aspiration and choose whichever one(personally I prefer max)) I don't know if cheats will work(ive had it where sometimes cheats will change the aspiration but not the lifetim want). However I don't think it works that way for all cheats

The above only work if you have nightlife!

If you have the renew you senso orb (which I'm guessing is how you got the grilled-cheese aspiration)Just fulfill wants, or do the cheat....Pull up the cheat box by, shift ctrl c...And type in "aspirationlevel 4" You don't use the "". You can also do any aspiration from -5 to 5. I like to do 4 because it's safe and I can still see when their needs go down. After you do the aspiration change, just do the renew you senso orb again.
Hope this helps!

Do This:

Spawn: Sims Modder
Wants And Fears
Lifetime Wants
Lifetime Wants Cycle Through ALL

Hope That Works If You Still Read This
It Works For ME

Use boolprop testingcheatsenabled true it's sooooooooo coooooolllllll!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

"Wants and Fears" is no longer an option on Sim Modder (the floating baby) and you can therefore no longer cycle through/change lifetime wants for Sims (at least through boolprop).

I used boolprop - changing aspiration doesn't change the lifetime want....

Activate the 'boolprop testingcheats true' and spawn the sim modder. It will look like a baby. Next click it, then 'Aspiration', 'Set Me', and finally the aspiration. Each want will have about three aspirations that it will fall in and each aspiration will have about five want that go into it. Some minor research maybe needed. After you selected the proper aspiration then go into the modder again, 'Wants and Fears', then 'Lifetime' and finally 'Cycle Wants for Current Aspiration'. Do this last step until desired lifetime want is achieved. You cn always change the apiration again without affecting Activate the 'boolprop testingcheats true' and spawn the sim modder. It will look like a baby. Next change your aspiration that goes with the desired lifetime want. Each want will have about three aspirations that it will fall in and each aspiration will have about five want that go into it. Some minor research maybe needed.the want, or just select 'Cycle Through ALL Lifetime Wants' if your not sure what you want, or just to lazy to research.