26 years old, married for 2 years now. My husband is 41 years old

 "I'm 26 years old, married for 2 years now. My husband is 41 years old. So, It happens that my husband impregnated a certain girl, ( a month pregnant) & now her parents have brought her to our home, pressuring him to marry her by force.

It's been almost 2 weeks & some few days since they brought this lady here to my house. She's 2 years older than me. She doesn't even talk to me nor greet me let alone response to my greetings unless she wants to say something very annoying or bring issues.

My husband insisted that she stays in the visitors room for now but, this lady goes into our bedroom and use my things, severally I've seen her wearing my clothes and using my towel,i complain to my husband but she pleads that i should ignore her, since she'll soon leave & he'll usually give me money to get different ones to replace them, but whenever i replace them, she goes into my room in my absence & picks another one especially my towel. Each time i try to ask why she's using my things without permission, she'll pick quarrels with me 

My husband has tried to take her back about 5 times, but her parents are refusing. Just 2 weeks this lady has already started causing trouble with me, making my home a discomfort zone for me

My main issue right now is; I'm supposed to go to school for my studies. Now, how am I going to leave my husband's house, leaving that girl behind? To make matters worse, I'm also pregnant at two months. Please help. I need your advice & guidance"