I am not trying to upset you, you still have strong feeling, will and hope for him.
However Shy,
When a man loves a woman madly, he can do anything to be with the woman, and make it to work FOR ANY COST. You certainly have not seen a love blinded man's capability and force.
Your ex does not love you. He actually plays with you using sweet words and gesture. Why don't you see the picture and accept it?
I will cancel the job interview if the only purpose of getting the job is being close to him. You will be disappointed. If the job gives you a better opportunity for yourself & career, you are willing to build a new life there with/without him, then please pursue.
Good Luck!