God made us to be emotionally stimulated ~ which means we must closely guard our heart. Failing to guard our hearts puts our body at much greater risk of falling to temptation.
Above all else, guard your heart, for it is the wellspring of life. Proverbs 4:23
It's easy to say "oh I'd NEVER do ________ physically" .... but how about emotionally becoming attached? Our hearts & emotions are funny things ~ they can get away from us quickly if we aren't on guard.
Spend some time studying the traffic light graphic on page 139 and the different stages of emotional connection!