Or it could have been that the deal fell through after an amount of time passed, came back on the market and someone else bought it. If you are outbid on something and it comes available again, the other party is not responsible for following up with you. Although they should.. it is not mandatory.
Who knows? contact your origianl Realtor or the sellers Realtor and find out what happened.
As far as your bid, a year later you may not have any recourse. You would need to prove teh agent withheld your bid to be able to have a case. Was your offer in writing, accompanied by a prequailifciation letter and deposit check. Did you save any communication between you. You can contact the agents managing broker but it is a year later.