Now I am going to make you even more envious.
We live here, having spent the las few years coming out for three months over Christmas and New year, we took the plunge last year and don´t regret it one bit.
There are more than enough restaurants etc open over the christmas period, some tend to close the first week in January for a couple of months or if they need refurbishment etc.
As "itsmeagain" mentioned, the lights are fantastic although the camara have cut down a bit over the last couple of years, also the fireworks over new year are great with a super atmosphere on the avenida.
Come and enjoy.