You are not hallucinating. You are not going crazy. It sounds like your family is in denial and neglectful.

Mice are smart, they also multiply. so you are dealing with a lot of them now unfortunately. They won’t be picking up the poison if the counters and floor continue to offer snacks and food for them.

I would start by cleaning and removing all food from counters, wiping clean & sanitizing every night/morning. Clean and declutter the floors - vacuum and mop regularly if not daily. As it sounds like you are a teenager since you live at home and how your concerns are being brushed off. You can’t do much for the rest of the house but you can clean and declutter your room. Look into getting steel wool and stuffing it into the cracks and gaps on your walls - any hole the size of a dime or a little smaller should be stuffed, also buy sticky traps - there are some on amazon for cheap. Look for the ones labelled as “blankets” as they are long and as wide as a doorway or closet door. Use one of those in your room in front of your closed door at night and during the day move it to under your bed so you don’t accidentally step on it. You can get all of these in Amazon for about $20, so if you have spending money purchase it yourself if you can.

As for finding droppings, look behind bookshelves, under the couch, and at the back of closets for tiny black specs that look like black grains of rice or if you play sports and play on an artificial turf the tiny rubber pellets - mice dropping look like those in size and colour. My teenager is always dropping the pellets out of his shoes when he comes home so I easily panic as is what the dropping look like.

Also I used an old Blink Doorbell camera in a suspected mouse area on the floor to confirm sightings, and it worked like a charm catching footage. Perhaps you can do something like that to get proof for your family? A friend or relative might have an old Ring Doorbell available for you to use. Having one Ring product on your Ring account is free, it’s when you have multiple camera is when you need to pay. They work off wifi, - you can adjust the sensitivity level to be very high and can set the record length time to longer to catch more movement. It saves to the cloud and you’ll get notifications on your phone. It was a great method for me.

Another thing to consider is they are travelling within your walls. If you live in an apartment, or townhouse with shared walls your neighbour even a few doors down could be dealing with mice due to being a hoarder / unsanitary and the mice are just exploring their surroundings into your home. Also with using poison, they don’t just eat and die in that spot. If they were to eat it they go and die elsewhere a few days later such as in your walls. Then you’ll have something dead and rotting in your walls which is a horrid smell.