That is not true. You might love someone to a certain level.ALWAYS. And depending on the accumulating of the situations of how that person is, you will love them more or less
If you would have a kid that will spit on you, hit you, vile racist, steal, being a killer, a sadist that will enjoy torturing people, that will kill his mother (your wife), etc... I can guarantee that you will love him less and even hate him.
These are very extreme cases, of course and I am not saying that being homosexual is comparable, basically because being homosexual would not be in any degree of negativity or disappointment in my scale of values (but for some people yes and in different degrees), and I am not saying that anyone here would hate a kid and would not love their kid because he is gay, simply, they would love them less, even if it is from 100% to 99,99999%, basically because in their own words, they would be disappointed because he/she would not fulfill their dreams