I guess I would ask my inner child self, whether those 6 years has mean't that your boyfriend is your soul mate, you know? That connection left right and centre.
I mean, chemistry is chemistry. We as women will always have that with a man that just ticks those boxes.
Depression is real, it clouds our minds a lot but then, to get out of depression we need laughter, love and a whole lot of understanding and doing things we love.
Maybe access your current life, outside of relationships and chemistry, such as hobbies, things you love you have never looked into, thinks that you know would make you smile daily like some plants in a garden that you look at daily and nurture and water or an art class something outside of all of this so you can find what you love in life that belongs to you and take it from there.