Your bet-sizing is off here. You are betting 50 cents into $1.37 pot with a possible flush draw. He is getting a little worse than 4-1 odds to chase his draw (with implied odds basically giving him the correct odds to call). Therefore, villain is not making a mistake by calling and we do not win unless we force our opponent's to make mistakes. Again, we gain when we cause our opponent's to make mistakes. I would personally bet about $1.05-$1.10 on the flop. I like to bet about 2/3 to 3/4 of the pot with a potential flush draw out there.

Good luck kind sir and keep up the good work!