The only rule Muslims know is to win. It does not matter how. All rules can be broken as long as they win the war. They can lie, they can deceive, they can break their treaties as Muhammad did, they can ambush or use terror, assassinate, massacre the children and bomb civilians. Muslims can even kill each other as long as this improves their chance of winning.
It is propaganda that people, who had lived a full life of heterosexuality, were married and had children, were denying their real sexuality all that time. There is historic evidence that entire populations can convert to homosexuality under certain conditions.
The world of Islam is a world completely distinct from ours. Muslims have a different set of values. They look at the world through the contorted mirror of Islam and everything they see is warped. That is the only reality they know. Islam is their only point of reference. Therefore when they commit the most dastardly acts such as murder of school children, they genuinely don't know that what they are doing is evil.