Becky Armstrong is one of my favorite Thai actresses, I'm a big fan of her outstanding acting. If someone is asking this question, it proves her acting skill is very realistic. One who has seen her acting in the Thai GL series GAP against Sarocha Chankimha will definability think this question.
About Becky Armstrong's sexual orientation, she officially never mentioned anything about it. As per I know, this is the only part of her acting career, celebrities keep these kinds of things secret to keep their fans engaged in thinking about and discussing them.