The direct equivalent of "love" is 愛 (ai) in Japanese, and this is a very big word — perhaps even bigger than English "love". English people often say "I love pizza", "I love New York" and so on, but Japanese people very rarely use 愛 with inanimate things. Even between two people, 愛 is generally thought to be something they gradually gain months after beginning a romantic relationship. Some western people living in Japan use 愛 too casually, which sometimes even embarrasses Japanese people.
There is another word, 恋 (koi), which can also be translated as love. "I fell in love with someone (at first sight)" is 恋に落ちた, not 愛に落ちた. See: Love in the air: 愛ｘ恋 {あい vs こい} However, 恋 still is a bit literary word; we do not say 恋 out loud very often when gossiping. When people casually say "You have a thing for her?" or "He has a crush on her", 恋 rarely appears, either.
Instead, 好き (suki) is used all the time in such casual conversations, and this word literally means to like. This is a very handy expression; in a situation where English speakers may say "I'm in love with him", Japanese people often get away with just using 好き.
So in conclusion, the concept of love is different in Japanese; there are at least three common words to refer to it. You seem to feel Japanese people overuse the word love, but I feel it's the other way around. Japanese people do not frequently use 愛 or 恋 in "girl talks", so it's probably the translators who needs to add the word love to make sentences more natural to the English-speaking audience.
I think this article is good: KOKUHAKU: JAPAN'S "LOVE CONFESSING" CULTURE
