Love
Since "love" is in the title of the movie, it is not surprising that it is also the main theme; however, it is not your typical Hollywood love story and the main character can sometimes be rather unlovable; he is angry, hen-pecked and has a niche company that gives rise to risible comments. However, when he does fall in love, he falls seriously and he respects love as a concept. He recognizes the importance of following his heart (he follows Lena to Hawaii). He understands the importance of opening his heart up to allow the other person in (after pretending that he was in Hawaii by sheer coincidence he admits that he actually went on purpose, trying to spend time with Lena) and understanding the importance of honesty, choosing to be up front about his unfortunate situation with the sex line rather than hoping she will never find out. His attitude towards love and the need to take it seriously and with honesty reaps rewards since the relationship's foundations are solid and at the end of the movie it really does seem that the main couple "live happily ever after".
Negative Effects of Lacking Love
While this is a movie essentially about love, it is also a movie that shows the negative effect that a systematic lack of love can have on a person. Barry is the poster child for a man who lacks love and an outlet for his own emotions. He is constantly derided and emotionally abused by his sisters which can make him feel as though all women feel as negative about him as they do. He is lonely, because he has a lot of love to give, and no specific outlet for it. This can make him angry because all of his emotions build up and explode. It also leads him to make very bad decisions such as calling a sex line that ultimately backfires as the owner of the sex line tries to extort him. Lacking love brings out the angry and negative side of a person, and prevents them from showing their capacity for love, or for feeling good about themselves, and the way in which Barry shows this is one of the themes of the movie.
Emotional Abuse
Barry is hen-pecked. He has many sisters who constantly tell him that his job is ridiculous and who look at what he sells and markets rather than how successful he has been in actually marketing them. Because he only hears negatives about himself, these are what he believes, and because these negative things are being said by women (in this case, his sisters) it takes away his confidence when it comes to having any dealings at all with women. The theme of emotional abuse is interesting in the movie because it shows how it can chip away at a person's sense of self and prevent them from moving forward with confidence or seeing themselves as anything other than what their "abuser" tells them they are.
Coincidences
One of the lesser themes is that of bizarre coincidences. Several things seem to happen to Barry all in one day that all lead up to his having a life-changing experience. He witnesses a terrible car wreck. He finds a discarded harmonium (that he just happens to serenade Lena with at the end of the movie) His sister has a family picture on her desk at work which Lena sees and is immediately drawn to. He also asks Lena to believe in bizarre coincidences (really, what are the odds of his business trip to Hawaii taking place the same weekend as her conference?) and these run through the movie as a gentle and amusing minor theme.
