That is horrific. I hope you reported both the incident and your suspicions about your neighbors to the police.
I think the fear of becoming death targets lurks in the minds of most transwomen. Not to mention anyone who dresses or behaves outside expected gender binary and hetero "norms." Even my supposedly "Godly" missionary friends brag on what they'd do if they saw a man dressed as a woman in a public bathroom. Sickening.
However, many/most people who transition do so only because not transitioning would likely result in suicide anyway.