Why do most people not like change?

So for the past 4 months i have been living at my moms house while going to school,house-sitting and taking care of my cat. She went on a trip with my stepdad for 2 months and they thought about moving elsewhere, which at the time that was a possibility.Them today My mom brought up the news to me that they're going to sell her house after they get a marketing analysis. After living there for 4 months and going to school and now these changes to my life are impacting me because my parents have been supporting me while i go to school and providing for me. My parents are retired and they want to move out of state or stay here. They are not sure yet. I feel like I'm "hanging" but i know that the benefits they have such as retirement,social sec, etc. They have no other sources coming in, they have a mortgage,it's complicated but if they keep this house and want to travel they can't afford that. They would want to finish the basement and put in the driveway, but that costs money too. I will be moving back to my dads because i know he provides the most for me than what my mom can do for me right now. My mom has never had steady employment through her life, and my dad has a steady income and a really good job that pays him well. I guess i should of stayed at dads in the first place but with my cat,I'm concerned about her cuz someone needs to take her when my mom/stepdad move somewhere,cuz i dont think they want to take care of her and they want to hand her over to me to take over.
Added (1). Trying to figure out what to do next or how to take care of her, my dad doesn't like having pets in the house because he will be moving out of state w/in 4 yrs from now after he retires. After i get my certificate I will take over the care of my cat if she is still around. Things are difficult for me to handle right now cuz life does change and it doesn't stay the same, and change is really hard for me to deal with.

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