A dreadful realisation

Affter chasing relationships and yapping to God about wanting a girlfriend. Suffering in one sided love for 5 year's and seeing the current state of life . I have came to a dreadful realisation that no matter what , If a girl comes in your life , you will have to invest so mucb time and efforts on her and same goes for girls when they love a boy . Eventually they are gonna leave , and I feel the need for relationship is also due to chemical reaction in brain when a person comes in life for you when you are alone . I feel no relationship or even marraige can heal or create a difference . Maybe idk I maybe wrong as well. But I feel we are chasing relationship not for love but to fill the emptiness we have in life . Eventually we all go in grave alone not with partners. So idk