Girls, but also guys, how do you get over people you dated?

I'm usually a pretty self-reliant person, but I'm going through this break-up that I'm struggling to cope with. It's taking my attention away from my job, my interests and even my health as I don't feel energetic enough to woke up and I handle stress by smoking (which I usually don't). Any advice on how to switch mindset or what things to do to stop self sabotaging would be appreciated
Updates
+1 y
* I meant energetic enough to work out
Girls, but also guys, how do you get over people you dated?
Post Opinion