Your question essentially boils down to whether someone can find a RIPEMD-160 collision.  Your address is a hash of your public key.  An attacker doesn't need to discover your private key, which has a probability of approximately 1 in 2²⁵⁶.  They need to find a private key whose public key generates the same 160-bit RIPEMD hash as yours.  The odds of this happening are 1 in 2¹⁶⁰.

This is still  astronomically large.  You can rest assured that your coins are safe.