"I broke up with my boyfriend last week."
Hmm my Japanese teacher taught that, koibito, 恋人, is more accurate for boyfriend/date.
I thought koibito was for couples/lovers/lover/person who is dating etc and that kanojou and kareshi were more specific, I might be wrong tbh
I love that it let's me just toss "た" at the end leaving off the 'ます' form. It never allowed me to use informal stuff like that before the update