Prepositions have a habit of changing between languages. English falls in love with; Spanish enamours itself of.
Me enamoro de ti · Me enamoro de él · Pienso en ti · Pensamos en ti · Pensamos en ella · Sueño con ella · Sueña con él · Depende de ella
The teacher's argument for treating this with curiosity instead of as a memory chore. Falling in love with involves the other person in the process; of feels much more detached.
The practical payoff: looking at it with a curious, analytical eye is what makes the difference stick. Mindless memorising of "de here, not con" does not.
With soñar con, maybe when people began describing dreams they felt the other person was involved, participating. Modern beliefs have moved on, but the language may still hold the old one.
Con is the exception to the mí and ti pattern: it fuses into one word, with a -go arriving from nowhere.
Compare de mí and para mí, which stay as two separate words.
¿Quieres venir conmigo? · ¿No quieres venir conmigo? · ¿Por qué no quieres venir conmigo? · Tienes que venir conmigo · ¿Puedes venir conmigo? · Sueño contigo · Voy contigo
Ñ is the only letter Spanish has that English does not: an n with a squiggle on top, pronounced n-y.
The o splits under stress here, exactly as in dormir. There is really no way to know in advance whether a given verb will, but if it splits for one stressed form it splits for all of them.
The dictionary prints enamorarse joined up, but do not let that fool you. There is still an -ar verb in there, enamorar, with the se merely hooked on.
Me enamoro · Estoy enamorándome / Me estoy enamorando de él
Sí is both yes and if, which lets you build longer sentences.
Depende de si quiere ir.