There are sometimes a person may have or have the right to blame others for certain things in his life but people will not see him in a good way if he keeps blaming others for everything that happened or has not happened in his life, he should at least try to change or improve his own life.
Some events or problems may occur in a person’s life when he was a child, a baby of corse he could never have the power to change it. in that case, I think solving that issue is the grown ups responsibilities who are in his life most of the times that is the only situation he may blame others for they way his life is.
Of corse that dose not mean a person may always just blame others, he should always try to improve himself and his life, his way of living since he is an grownup. No one can go back to the past to change it, at least in the real life (not fiction) but people could change their present and future if they worked on it on daily basis.