I am a student, so maybe this is completely useless advice coming from me...
I teach one of my friends on and off (lets make her name Sue). Sue always begs me to teach her dances - she never wants to concentrate on the actual moves, and combo's. Her dad is a musician, so I find it really strange that growing up with a musical background that she also struggles to find the beat.
She can remember dances just fine, but she seems to act as though the dance and the music are 2 seperate entities.
I used to struggle with finding the beat, and I feel that sometimes its quite easy to hear the beat if I sit down and just listen to the music for a bit.
In my classes we only get the music once we have learnt the dance, so when I get a song at the end of learning one of our dances, I'll sit and listen to it once, (JUST listening) then the second time around, I close my eyes and imagine myself doing it. It helps me find the beats in all the right places because im not concentrating on DOING the moves.
Dont know if this'll help... try it out?