This is exactly how real world works. You always have to find right people into any team with different skills to make the job done.
Talking about your problem what you have to do is to master design thinking, social and business skills. Read Medium and Quora every day and practice more if you want to become better in these domains yourself or find another freelancer to work together, however, the only way to become an adult is to learn new skills all the time and to rely only on yourself. You, may be, will not become a talented graphics designer but, I can promise you, your work will at least feel and be usable (not look) much better.
P.S. everyone is a designer and design is not how it looks, it is how it works.