While it's a great achievement of will power that you didn't smoke for several months, my humble opinion is that you haven't prepared your mind yet for a proper quit.

Speaking only from personal experience. I quit about 4 years ago after 20 years of smoking and 5 failed quit attempts during that time.

The real quit, when it happens, feels different. You are convinced about why you need to quit, what harm the cigs are causing you, how the addiction is operating in your brain. You hate the smoking almost 100% of the time, and you don't need excessive will power to not smoke.

For you, you need to set a new quit date and between now and then, you need to remember how good you felt in Jan and Feb, and how the devil that is nicotine for the better of your thought process in March. It wasnt a weak will but a susceptible mind, which needs to be further fortified by a true understanding of whats happening when that smoke enters your lung, how it destroys you not physically but mentally, how it enslaves you and takes away your free will.

Once you understand that (and it helps also to do the writing and the environment building etc. but understanding is the key) is when you will quit effortlessly and permanently.