Simply replace the unfilled areas such as "" and "[date]" with your information.
I just wanted to wish you happy holidays. We're both so busy and I wish we had more time to spend together. Maybe we can get together sometime before New Year's?
If not, I'm sure we'll run into each other soon. Are you going to [name 1]'s thing at the [place]? I hear [name 2] and [name 3] are going. Have you seen their new kid? [name] is his name. Adorable!
Anyway, enough banter. Email, write or call. Or come by for a rum and nog.