You have so many blessings in your life. Your children love you and want to give you things. You have a handle on yourself it seems.
Pining for what we don't have often gets in the way of appreciating what we do have. I'd hate to see you in that place. It's a not nice place to be.
I'm so sorry that you are having a down day today. Hopefully cranking up the stereo with some Christmas music or AC/DC or Johnny Cash or your music of choice will put you into a bouncing mood. If not, I shall send Tig out. It's contagious, you know.
Rockin' around the Christmas tree will certainly get your endorphins up.