I know this is an old post, but I thought it would be fun to answer it. I'm originally from the U.S. Love is something that is misinterpreted from country to country. I spent some time traveling to other countries. In America love can be taken two different ways. Love is seen as "sex" or it can be "a strong emotion of regard and affection." The second meaning is what is used in this song. In other words, love is a feeling. So in this song "Making Love Out of Nothing At All" means that he fell in love with her and she didn't do anything to make it happen...it just did. He doesn't understand how he fell in love with her when she did nothing to try to win his affection. If you watch the music video it starts off with a guy who is a musician and a girl. They are both saying goodbye because he has to go on tour with the band. He wants her to go with him but she refuses to come. I won't spoil the rest of the video. Just search online and you will find it. He truly loves her, but she doesn't see a point in having their relationship continue because they are both leaving.
This is a highly romantic 80's song that is still cherished to this day by love birds. I hope I cleared this question up. This is just my interpertation of the song. Someone else may have a different opinion.