Cat peeing in floor

Brittany

so we have had our car for about 2 yrs now. shes fixed, shes about 3 and since september last yr shes started peeing in the floor. ive taken her to the vet 5 times, they say she has bladder crystals, shes been on anti biotics 2 times and shes on a special food but none of it helps. our last option is some kind of injection which we are doing next week. My thing is, she pees in corners, on our clothes and our beds. We shut her out of rooms but she manages to still do it. she even pees on our bath mat, and when she hears us coming she runs out as if she knows she has been bad and hides from us. Im wondering if this could be behavioral, and if so how do we get her to stop? Shes always been an indoor cat but honestly we want her outside or living with someone that can handle it. Im 4 months pregnant and cant have my baby around that smell or have my cat peeing on my babys stuff. what can i do? Can i put her outside? help. :/