I don't know what to do

Ok long story short, I have a 20 month old with a guy named Bobby. We broke up a while back and now he gets visitation with our daughter. He was just getting her every other weekend but when I would bring her back home she would ask for him and say I want Daddy. I'm not sure why she does this because when we were together she always wanted me. It's hard to see her like that and it tears me apart that I'm doing something wrong. I decided to let him have her 1 week a month and 11 weekend in the thought that maybe it will make things easier on her, sounds stupid I know how would going longer make it easier I know but it's hard to explain. I'm also scared though that it will be very hard on her too because when I went into premature labor with my second child and was in the hospital for a week, her and my finace came to visit and when he had to take her out of the room with him she just screamed until she came back. I'm just at loss with what to do. I think in a way it will be good for her to have more time with her Father and also that she gets that one on one time ( I don't get to do that often having a preemie at home and most of the time being home by myself with both of them) also none of family lives close so she doesn't get to see them often and I don't have any friends around this area so she doesn't have any kids to play with and there she has some cousins around her age that live right up the road a few blocks. There are pros and cons to it all and I just don't know what to do. My fiance thinks it will be fine and that it will be good for her I don't know what to think and other people I've talked to give me mixed answers. I need some advice. My questions are do you think that is too long for her meaning she's only 20 months old, and that she'll be even more hurt and confused and also if any of you have had similar situations did your children do what she does when she gets home and if so how did you make it easier on her? Please any advice is needed she is supposed to go on Friday. I'm gonna go nuts not having her here and being able to say goodnight and good morning and giving her hugs and kisses and etc.