To me it sounds like you are way too harsh on yourself. We all need help sometimes, and that includes professional help. Your therapist is someone who is qualified to help you work through the things you are struggling with, and to help you cope with overwhelming feelings. That doesn't mean you "rely" on your therapist for everything.

As for when you should quit therapy, that is a very individual thing, but I think it is important to feel like you can stay with a therapist for as long as it feels beneficial to you. If you feel like the therapy is working, that's a good thing, and it doesn't make you weak or dependent or any of those things. In fact, I believe that asking for help is sometimes the hardest thing a person can do; it was hard for me, and scary as hell, but I feel so much stronger from having done so. Asking for help is a personal victory, in my opinion, especially because we often expect way too much from ourselves. We feel like we should be able to handle everything on our own, but we can't, and you wouldn't expect the people you care about to do that, would you? So why do you expect yourself to?

My therapist always tells me to be kind to myself, and now I am going to pass that message onto you. Be kind to yourself.