Blockchain – How many years can an unconfirmed transaction be confirmed?

Let’s say you make a trade and it doesn’t get confirmed for several weeks due to low fees. The transaction is then mostly removed from the node’s mempool (and My Wallet ignores the transaction and allows the coins to be spent again).

But since the transaction is signed and broadcast publicly to the network (all nodes), how can anyone rebroadcast the transaction and ultimately confirm it years later if the coins used in the transaction are not spent on ? meantime?