Divorced mother helping daughter get to know her new partner

I have been divorced for 11 yrs from my daughters Dad. We still do a lot of holidays and birthdays together and had another child who is 3 years old.We never remarried and parted 1 year ago. I found someone who is 14 years younger and my daughter wont have anything to do with him. She doesnt know him but tells me that she doesnt feel comfortable around him. They've met 3 times and I have known him for about 2 years. How can I help her get to know him? She tells me if I choose him then I can only see her every other weekend!I don't know where to start with this...