Do I have to buy directly from realtor seller and not use my realtor?

My husband and I are interested in buying a house and we are already in contact with are realtor. We gave the info of the house we want to are realtor so that she can contract the realtor who's seling the house, there's was no answers from them and it's been I week so I called the realtor who's seling the house and he pick up fast. I gave him my info and we made a date to see the house at the end I have him my realtor name and he cancel my appointment to c the house because he has a pass problem and don't like my realtor. My husband calm him down and we continue with the appointment to see the house . A day before seeing the house he cancel are appointment because my realtor was trying to do her job and contact him. Now he wants us to see the house put we have to sing a contrac before seeing it . He wants us to bye the house from him and not use are realtor, we also try to use someone else to represent my realtor and he don't want that. Now here's my question can he do that?