Is what the questioner did towards her mother who committed suicide a sin, and what is the ruling on suicide and the fate of its perpetrator?

Obeying and honoring one's mother are duties upon the child, so long as it does not involve disobedience [to God]. And everything that displeases her must be avoided. If the mother's anger is due to the child's disobedience in a permissible matter, then the child has contravened Allah's command and His injunction to be kind to parents, and must repent and seek forgiveness. However, if her anger is due to disobedience in a forbidden matter, then there is no sin upon the child; because there is no obedience to a creature in disobedience to the Creator. As for suicide, its ruling for a Muslim is as stated in previous fatwas, but for a disbeliever, he is among the people of Hellfire even if he does not commit suicide.