Why is he paying for my phone

My fiance decided he needed space. I freaked out because it was all of a sudden he said he needed time to breathe but yet a few days before he said this everything was OK with us so I was trying to call him text him asking him why he did this and all I would get when I did get a response was that I was annoying pathetic stop texting him this has gone on for 2 weeks. I finally seen the real side of him and he is abusive. I have a phone and phone number on his account that he gave me when we were together. He told me I could keep the phone. So I texted him telling him that I got a new phone number and he can't have my new number. I thought he would be relived that I won't call him or text him anymore because I have this new number instead, he said since you are getting a new phone number give me back my cell phone. All I do is bad mouth him on it... I reminded him that he had given it to me, he said if you continue to bad mouth me I will take the phone and blacklisting it. First of all, why is he letting me keep a phone and phone number that he is paying for? The only reason I want to keep the phone but not the phone number is because it's an expensive phone have the money no for a new one. If he don't want to be with me than why pay for it and get upset when I told him I was getting a new number.