My question involves defamation in the state of: Ontario, Canada

I have come across a website in which they have taken 2 of my pictures off Facebook and they have put them side by side and have pointed out that I have gained a considerable amount of weight.

Do I have a case against them for stealing my images?
They have a disclaimer saying "you must have permission to submit photos to this site" but clearly I didn't submit the pictures

Should I ask them to take it down first or do I have a case?
Please respond ASAP