Outnumbered by Daughters

The book is an adult fictional novel, based on a young man's struggle with sadness, tragedy, complicated romances and family life. He attempts to bring up twin girls and an older stepdaughter as a single parent through their middle school years.
He encounters all sorts of problems that readers could relate to in their own personal life, involving mixed emotions and hardship, including his own complicated and failed romances on his journey through this stage of parenthood.
He has to deal with embarrassment and overcome all sorts of new experiences as he tries to understand the problems and needs that young girls have to face as they grow up.
The girls' teenage years present him with a completely different set of problems, but he does at least have better success with romance, resulting in a wife, new daughter and stepdaughter finally completing his family.