If there are other “Gods” and other “Earths,” do people that commit suicide perhaps go to another “Earth” with worse circumstances to work through?
In short, no. Not those who commit suicide, nor any others, will be reborn or reincarnated at any level to any other world. This can easily be substantiated with a few scriptures. First, Paul teaches us in Hebrews 9:27:
“And as it is appointed unto men once to die, but after this the judgment:”
Amulek teaches us in Alma 34:32-33:
“For behold, this life is the time for men to prepare to meet God; yea, behold the day of this life is the day for men to perform their labors.
“And now, as I said unto you before, as ye have had so many witnesses, therefore, I beseech of you that ye do not procrastinate the day of your repentance until the end; for after this day of life, which is given us to prepare for eternity, behold, if we do not improve our time while in this life, then cometh the night of darkness wherein there can be no labor performed.”
Also, he teaches us in Alma 11:45:
“Now, behold, I have spoken unto you concerning the death of the mortal body, and also concerning the resurrection of the mortal body. I say unto you that this mortal body is raised to an immortal body, that is from death, even from the first death unto life, that they can die no more; their spirits uniting with their bodies, never to be divided; thus the whole becoming spiritual and immortal, that they can no more see corruption.”
As we can plainly read, once we die (one time only) we will be resurrected, never to die again. And this life is the time we have been given.
In Abraham 3:25 we learn that we are here to be proven and to see if we “will do all things whatsoever the Lord [our] God shall command [us].”
Putting these scriptures together helps us to understand this basic part of the plan of salvation. This is the life that is given us, and another one will not be.
I do think that it is important that we understand, as well, the justice and mercy of our Father on judgment day. We are not to judge others as to their potential for salvation or not, nor can we anticipate who the Lord will and will not accept into His kingdom. We do not know the state of other’s minds or their accountability level. So we leave that to God.
We cannot and should not presume that those who commit suicide are doomed or saved. To presume that someone who committed suicide deserves a worse situation is as unfair as presuming that someone who committed suicide is automatically unaccountable. We leave that to God.
Either way, just as all of us, they will stand before Christ on the day of judgment and answer for themselves per their agency. And God will deliver unto them mercifully and justly according to His law. (See also Alma chapters 40 and 41.)