I agree with Anne 100%. You will find in this forum not just support but plenty and good information a reading that would educate you about nicotine addiction, and that in turn will help you with the mental process of freeing yourself  from nicotine.

I will offer a scientific angle to this.

When you say "my brain seems to think I've had my fun and it's getting real now" this is not exactly what is happening. Your brain has many parts and the nicotine addicted part of your brain will manipulate your rational brain to think that "one cigarette is all you need to get over the depression", or , "it's no fun now".

What your addicted part of your brain is actually "thinking" is: "Nicotine is as vital to my survival as food and drink. I am now been deprived of this molecule, and I will do everything possible to get it back" Sadly that is what nicotine does to our brain. 

Cigarettes do not help with depression. They make it worse.

Millions have quit and so can you. You have made it so far, you can do it, persevere, educate yourself on the subject and post here as often as you need.

Hi Better,

You have past the first two of the icky three’s!
https://www.verywellmind.com/what-are-the-icky-threes-2824685

Keep up the good work!  We gotcha!

I am a three weeks also. Yoga helps me a lot. Hang in there, we can do this!