Should I wish him a happy new year? I have not heard from him in a few weeks.?

My friend who is going through a tough separation, just stopped writing to me about three weeks ago. My last email to him was very polite and I suggested for him to call me if he needed something. He was taking about two weeks vacation and was indirectly trying to make me his rebound girl and spend the holidays with me. I was never rude or nasty to him, but rather platonic at all times and he got the point. I explained that he has a lot on his plate and this is not the right time to see each other. Today is my birthday and I have heard from everyone except from him. Should I write him a short e-mail to wish him happy new year or should I leave it alone?