The holidays was the one thing I never had any guilt about after I left. I never thought the explanations the witnesses had were good enough to deprive ourselves of a little joy.
They also told us it was okay to buy presents and give them out on other days without reason, just not Christmas or birthdays, so gift giving is a sin on particular days and okay on others? What a crock! Decorating your house is actually a good thing and encouraged by the society, just not lights at christmas or any colors associated with worldy holidays or seasons, again I say crock!
Go ahead and celebrate - I think one of the few teachings the witnesses got right is that God's people are a happy and joyous crowd, so go out and buy those presents, have parties and love each other every day. Including christmas, birthdays, thanksgiving, st. patty's, and any other holiday you like.