I'm envious of people who are in relationships all the time
Why are you envious of people who are in relationships?
I want to be in relationship but I'm not.
If you want to be in a relationship, you should make efforts for it. It's not ok to envy people for them being in a relationship.
My efforts will just go unnoticed, so I do not want to bother trying. This world only rewards the people who have money. I don't have time for relationships. I have to focus on myself to get my life right.
If you are truly content, then why are you jealous of other relationships.  You should focus on something that makes you happy so that you can forget about what upsets you.