It's certainly an unfortunate situation, but the truth is love is a choice. We don't have to feel "in love". We can choose to love although most people don't understand this. Love means putting the other before yourself even though it may not be reciprocated.
As far as the baby, it is also a fact that the child needs both a mother and a father to be well adjusted. There are emotional needs that only the father can provide. A single mother can never meet those needs and the father cannot meet certain of the needs provided only by the mother. Almost assuredly, another man other than the father will not love your child. In the beginning it may seem so, but most likely that relationship will fail in the end leaving even more scars.
That may not be the answer you want to hear, but as a counselor I see it everyday.