You can't be strong just wanting to protect yourself. If that was the case, then everyone ever in all the worlds would be strongest. The person with the strongest sense of narcissism and fear would be the strongest. And that kind of thing doesn't work.

You deserve better matey. And the Prince of Hope should never have to give up. Don't close yourself off Eridan. You still have a lot going for you and people who care about you. You saved my life, think you let me try to save yours?