How do you know if you are a failure at this or if you just haven't found someone who fits? What if the issue is you are just not ready to settle. Many people settle in order to avoid being alone. That works for them. Maybe it doesn't work for you.

As an experiment, maybe it's better if you just look for a friend instead of a romantic partner. Then if something happens, it's just a lovely coincidence. You will always risk getting hurt or hurting someone else no matter what. But if you just seek a friend instead of a partner, perhaps it won't seem like a success or failure situation.