People stay in love because they have values and habits that make them stay in love.
People fall out of love because they do not have the values and habits that make them stay in love.
Do you know why he left you?

I used to know two persons who lost their jobs at the same time and the same employer. One was like you because he was attached to his job while the other was happy because he was not attached to his job as he developed skills that others want to employ.
Do you have skills that others want??? If no, why not????