tired of fighting

im a single mum to a beautiful 11 month old boy, me and his dad was together nearly 3 years, my sons dad has kids with a previous partner, we broke up when my son was around 3-4 months old, ive been trying for him to see his son and have a bond with his son, but all i get is excuses as to why he cant see him, his other children live across the road from me he can make time and effort to see to go and see them but cant to come and see my son, im so tired of trying and wondering why my son isnt good enough, his family have no involment with my son either they havnt tryed, he makes me out to be the bad "mum who uses her child as a weapon to everyone" when that isnt true, i feel so down and depressed with it all, he dont pay for his child or provide for him he hasnt done none of that from him bein born, i dont ask him for anything or ever asked him to contribute to anything ive bought for my son. i dont want my son hating me for his dad not being in his life im stuck between do i give up or do i keep trying and hopin one day he will see sense and actually be there for our son? x