Dear Foreverhopeless, Welcome to PC.
You need not feel hopeless. So many of the people on this site have found ways to cope with depression. There are good options for you. I think you need to see someone for help. There is a lot going on with you and it may be difficult to sort everything out for yourself. A counselor or therapist can help you sort through all the tangles and help you see things more clearly.
IMO it is not surprising that you are feeling insecure and have low self esteem. You haven't been in a circumstance that would help you develop these skills. You are from a large family and may not have had the attention you needed. On top of that you were abused by someone you should have been able to trust.
You are a valuable human being with intelligence and insight. I know how easy it is to depend on the opinion of someone outside oneself to make us feel worthwhile. If you don't feel complete inside then you will allow someone else to define you. That leaves you vulnerable. If you can you should begin to build up a personal definition. Who do you want to be? If you need to feel useful and worthwhile you can volunteer to help other people or animals. If there is a community center available to you maybe take some craft classes or begin to study something you can use in the job market. Not only will these things help your self esteem but you will meet so many new people. It will open up a new world for you.
I hope you get the help you need. Good luck