How do you know blockchain forgot about it? I clicked your link and it says unconfirmed.
Blockcypher says it's a double spend. A few minutes ago the blocktrail explorer said that transaction didn't exist, and that the receiving addresses were unknown, but now it's saying the transaction is confirmed and the receiving addresses have coins in them.
https://live.blockcypher.com/btc/tx/8a73ed525dd603b6c8bc8d6b4ea8550e54f9f30a22588efc1c9fa6beea610138/WARNING: This transaction has been double-spent by 2bcd9c1e3df0ba96aad50798c6074..., be extremely careful when accepting this transaction!
This is the other transaction from the double spend.
https://live.blockcypher.com/btc/tx/2bcd9c1e3df0ba96aad50798c6074b5b2aa2b03b9a9d727172fc344fb095831e/