In a normal setting when a user deposits his SOL to create the wETH, where does the SOL go at the end when the wETH is settled? Where does the SOL go when it's released from the wETH?

The wETH pairs X amount of SOL with an ETH. When it's settled, it releases both the SOL and the ETH to the corresponding parties. When the wETH is falsely created, it creates the SOL it wraps.

You don’t deposit any SOL to create wETH, you deposit ETH on the ethereum side. That’s what the name means, “wrapped ETH”

wETH wraps ETH, not SOL.

So where does the SOL go in a normal transaction?

SOL is the gas on Solana smart contracts. In a "normal" transaction on Solana, SOL goes towards paying the TX fee itself.

In the case of the Wormhole bridge, there are transactions on both the Ethereum mainnet side (paid for in Ethereum gwei) and the Solana network side (paid for in Solana gwei). The only lossy factor is in the bridging fees themself which are typically a "flat" fee.