What are the motifs in Light a Penny Candle by Maeve Binchy?

Addiction is a recurring idea of the story. Tony Murray's addiction to alcohol is the great tragedy in Maeve Binchy's Light a Penny Candle. It brings out the fierce temper that is seen flashing earlier in the story and fills him with the defensiveness and denial characteristic of those addicted. It appears that he is rendered impotent by alcohol, but he refuses to see a specialist to confirm this. At any rate, over several years he fails to consummate his marriage to beautiful Aisling O'Connor, with whom he had been sexually aggressive while dating—and while his consumption of liquor had been limited.