The language or meaning of flowers is not absolute. It has evolved over centuries, but gained greatest importance during the Victorian age. Most flowers have several meanings that may be based on the color, shape, or even the way the entire plant grows. I suspect the meanings of baby's breath are due to its white color and common name. I only found purity and innocence listed for baby's breath, and at one site the meaning "festivity." As baby's breath is often paired with roses, I sure that is where you derived the "love" meaning, but baby's breath does not mean love.

http://www.buzzle.com/articles/list-of-f...

http://marriage.about.com/od/flowers/a/f...

http://aboutflowers.com/flower-a-plant-i...

http://flower-dictionary.com/list.html

Why Baby's Breath flower use to symbolize love, pureness, and innocence ?

Beautiful Baby’s Breath Picture : http://elstika.com/beautiful-babys-breath-black-background-pictures.html