Is this a question you've been asking lately? It is a good question. You'd think that with everything coming back to life, that mouse would want to be back out in nature where he belongs. But mice are commensal creatures. Unlike a parasite which lives in its host and does harm, commensal creatures live along side their host, deriving benefits from being in proximity. That means they are motivated to stay around you. So, the real question is, "Are you being a good host?"
House mice are basically freeloaders. Living in nature is too much of a downer, dude. That means they live in houses, not nature. It just happens to be your house they're living in at the moment. But it doesn't have to be. All you have to do is be a lousy host and your guest will leave.
How to be a lousy host for guest mice:
For crying out loud, don't feed them. No freeloader is ever going to leave if you give them three square meals a day. Mice are rodents, so there is really no shelf or cabinet that you keep food in, that they can't chew their way into. The safest place for food is in the fridge, a freezer or hard plastic containers. This is especially important for food that is in cardboard or paper packaging.
Don't give them snacks. Some unwanted guests may even stay if there are snacks around. Be sure to clean up crumbs around the toaster, jelly off the counter and all of the tiny things stuck to the kitchen table. Clean floor and rugs regularly. Don't leave food dishes or have beverages laying around the house, especially overnight. And don't leave a dry stack of dirty dishes on the counter. Stick those dishes in soapy water. If mice can find a snack, they'll stick around.
Don't offer your unwanted guest a drink. If you have a leaky faucet or pipe, you'll be creating a puddle that mice will enjoy. More often, mice will go to the rotted place they chewed their way into the house and get a drink from the liquid there. If you have mice in your house, it is important to address the conditions that brought them in. Make sure your gutters are undamaged and unobstructed. And, make sure they channel water away from your house--not down your walls. A wet wall will have rotted areas. Moisture is the death of a home. Mice could be the wake up call you need to get motivated on those important home repairs.
No one likes an unwanted guest. If you take away the food and water they need to survive, mice will find another house to live in. You may want to also consider getting a pest control company to do an inspection and give you some insight. The conditions that brought mice into your house could bring other damaging pests, like termites and carpenter ants. Don't let pets steal the equity you have in your home. Do the maintenance that is needed to retain the value of your home.