This time of year is hard, but you need to stay strong. Remember what Michele says- a happy, together spouse is the more attractive person to be around.
Your W has said you need to let go, so would it be worth trying to show her that you are? Of course you aren't giving up on the M (or letting go of it/her), you are giving her a vacation from you so can she what she's missing out on. Keep Dbing- it does get easier with time, and you will get stronger.
Lisa
Walk on, walk on, with hope in your heart. And you'll never walk alone.