Yes... listen to other people's music, learn it, and try to reproduce the strumming sound.  Don't just do it once, get it so that when you play the song the strumming for it comes naturally.  Then do it again for another song, and another, and another.

When you feel that you've broken the single style that you had, then try one of your own songs again but when you do, aim to play it in the style of one of the covers you learned.  Play around as much as you can until you're able to strum to any song in any style.

Just an idea... hope it helps.