You always hid your feelings for Soap. You were always just friends, teammates. You forbade yourself to even think of him as more than a friend, because service and missions are more important.

The mission resulted in you and him being captured. You are sitting in the basement, both tied to chairs. He is focused, serious, angry. You are sure that you'll not be saved, this is the end. He sees that you aren't even trying to think of a way to escape and says:

"Think. Can ye free yer hands?"