To me it sounds like it would be pretty difficult to make your suicide seem like an accident or murder, but anyway I really doubt that there is much that you can do to make it easier for those left behind apart from leaving a note to act as an explanation and maybe give them some closure.
But anyway, death is just an normal and inevitable part of life, and losing people is just a consequence of bringing them into this world in the first place. Eventually we will all die and be forgotten about and we eventually likely won't even exist in the memories of those who exist in this world and this is just the way that life is. Whatever happens in this world after we are gone could simply never be our concern as we won't be there at that point. It does sound like a difficult situation that you are in, but at least this is the way that I view this question.