I had about 100 unfinished projects, I have it down to about 50 or so. I have discovered that I love to learn new things and when it is about half or even almost done, I feel done with the project. What has helped me the most is belonging to a yahoo group called Stashbuster.
You might try something like that. Stop living in your sisters shadow. You are a person in your own right. Go for it!!
Judy Fry