As for the term "partner" -- I'm straight and lived with my boyfriend in 1979 and referred to him as my partner. Though I was only 19 at the time, I thought myself too old and mature to use the word "boyfriend." In later years, I have used the word partner for my husband. This is not a trendy new term that means anything other than what people using it want it to mean.
OP, you just need to have a conversation and find out what the dealio is.