Why do i smoke?

Ironically i had quit just fine for about 1 week with no problem it seemed.  But then i was on vacation and not in my usual routines at home.  My life is pretty stressful dealing with mentally ill husband and two todlers.  I have OCD and anxiety issues myself.  But why is it that i wanted to light back up right when i got back to my comfort zone?  for me i guess it is a deeply ingrained routine and the the cigs are part of that.  Then there is my trigger situations-- when the kids are screaming over something ( i light up outside of course), or when hubby has a dramatic issue, or when i am bored briefly, finish a project, first thing in morning and last thing in evening when everything is quiet.  Those are the big ones.  I see that i am using cigs as a crutch and as a reward.  I use them to fill spaces in the day.  I use them to escape anxiety from outside influences.  i use them to reward myself for a long day or a job done.  I have tons of hobbies and so that is not an issue but i need to learn to find a new reward and a new thing to do when i need that brief escape.  I think if i can discover those 2 things then i can start again and this time be successful