if the girl go out with a guy like that just because he treats her well...who knows if the girl will leave the guy for some other guy who can treat her better...
who knows how long will this last and if the girl will get sick of it...
Don't think about his height for a sec, think about all the other qualities he has. If they match with your standards, then who cares about anything else??
close your eyes and imagine a picture, in which you were watching yourself and him walking together in front of you, do you feel akward or any strange feeling? or do you feel happy and comfortable? you decide