my2cherubs, your children are very lucky to have such a loving and caring mother. I can tell you that you can be depressed and still be a good mother. But you need to be good to yourself too. I think christmas is such a big pressure on everyone to be "perfect" and it causes so much stress, i really quite resent it sometimes.
What a shame your DH has to work. Will you see him at all on Xmas day? A friend of mine's father is air traffic controller and always works xmas day, they have christmas later on. Could you do that? To be frank, your 2 year old wont know any difference and you could turn it into a positive for your elder child. Maybe have some pressies on Xmas day and hold some special presents back for when DH can be around. That way your DS gets two christmases and you have something to look forward to still while the rest of us are just slipping into anticlimax mode.
I totally sympathise with the debt, we have been there to pretty much the same tune,well, more to be honest, and its really bloody tough, things are pretty shit financially here too. It is a big strain and worry i know, its always niggling away, but sadly, i think we are far from alone in this.
Are there any local mother and toddler groups, you have to "shop around" as some of them are torture, i have posted many a thread berating them, but it seems that finally, i am making some friends.
I think you should go to the doctors, i have depression and it is shit, BUT it doesnt have to be that dark tunnel we are all so scared of. What i am trying to say is, you dont have to be in a dark tunnel of despair and horrendousness to benefit from some "help". I have been on ADs for the past six months and they have saved my marriage, if you had told me i was depressed i would have dismissed it, in fact, i did, lots on here, after posting some really sad posts people were more or less shouting through the screen for me to get myself to the doctors. Your doctor will not question your ability of your parenting skills, mine have never even been spoken about, no interfering HV as i specifically told my doctor i didnt want my HV involved as she is over sympathetic and patronising. It just gives me the boost i need to see the light at the end of the tunnel.
It will get better, i promise.