What really matters is how you feel about your own divorce. If you feel ashamed, then you'll feel ashamed. If you feel happy, you'll feel happy. If you do happen to feel ashamed, why? So your marriage failed. So what?
Many people's marriages and relationships fail. Many people get fired from jobs. End a career. Stop a competitive sport. Lose a game. Lose a promotion. We all have losses in life. Yours was just an interpersonal life. Sure, it can hurt, but everyone fails. You are not the only one.
Instead of feeling like a failure, try feeling courageous. Courageous to move on. Courageous and mature to say goodbye. Feel proud you tried, don't feel embarrassed because it didn't end as you expected it to. Life never goes as we expect it. That's how it is.
You are OK.