Complex sentence: When he finally stepped down from the presidency after eight years of hectic political life, and after years of civil war, he was relieved, and later stated, I was never so happy in my life as the day I left the White House.
Split into simpler sentences: When he finally stepped down from the presidency after eight years of hectic political life, and after years of civil war, he was relieved. He later expressed his relief, I was never so happy in my life as the day I left the White House.