Can Depression have cycles?

Hi all I've been dealing with depression alone now for 4yrs and I was wondering if there is some reason it would come back every so often? The sun is shrining and all is well compared to norm any input or critic welcome I'm tired of being on this yoyo I feel like cutting the string. Also consuling is out of pic, I live in a semi small town of dumbasses so its hard to connect or have any relation with em. If you need more info hit me up thanks