There are numerous synonyms for the phrase "was in love with," each conveying a slightly different nuance. Some synonyms include infatuated with, smitten with, enamored of, charmed by, captivated by, entranced by, bewitched by, besotted with, and adoring of. Each of these synonyms carries a distinct connotation and emphasizes a particular aspect of the feeling of being in love, whether it be a strong physical attraction or an intense emotional attachment. Ultimately, the choice of synonym depends on the specific context and desired tone of the writing.