Complex sentence: Towards the end of his life Heseltine became depressed by a loss of his creative inspiration; he died in his London flat of coal gas poisoning in 1930, probably by his own hand.
Split into simpler sentences: Towards the end of his life, Heseltine became depressed by a loss of his creative inspiration. He died in his London flat of coal gas poisoning in 1930, probably by his own hand.