Well, you're not a failure because you haven't landed a job yet, so dont think that way. Jobs are scarce all over..and I have been passed over on jobs that I knew I could do, in favor of someone else that got there first, or just flat out appealed to the company more.
If you are over 45 however, and you feel you are being discriminated against because of age, you can go to the labor board and report it.
Ya know, there are ways of finding out..maybe find a friend who is a bit younger, who has the same qualifications as you, fill out an app for a company on the same day or something...see if he gets hired..if he does and they turned you down, thats a sure indication of age discrimination and you can sue the company for whatever they are worth
Regardless, don't give up..it'll happen :)