(Matthew 6:33-34 KJV)
The verses above helped me much over some very hard days. I think they might be a blessing for you, too. If you think you cannot stand it anymore, just stand one day after the other and trust the Lord every day anew.
It also helps if you want to get rid of an addiction like smoking, by the way. Stop it one day, and get new power to refrain from it the next day... You do not have to refrain from nicotine forever, just for one day, and another single day, and another single day... If you have the strength to do it for a single day, you also have the strength to do it for another single day. I hope that this might help someone...