I think some people just have a knack for some things -
and others - try as hard as they can - just don't seem to be able to "get it"
I think it "just is" - and one learns to live with it and to compensate where and when one can.
Do you think your friend would welcome/accept someone else (you) picking out the fabrics for a project and then let her go with the rest of it?
From what you've said, she seems to be technically proficient with cutting, assembly, etc.