TL;DR
Send your Monero from RetoSwap to another wallet from where you use it. Do not use it within RetoSwap for payments. Is that what it boils down to? Then I would like to remind you that in practice it makes sense to use two wallets. One for receiving and one for sending. The one for sending will be replenished by the one for receiving. https://monero.town/post/5701064