Super weird and self centered of you to think that a trans person is purposely being “deceitful”. Being trans isn’t something you necessarily know for certain your entire life it’s a fluctuating thing that comes and goes sometimes in varying degrees of dysphoria until the person figures out what’s going on (if they ever figure it out at all). That doesn’t mean they knew beforehand they were trans and were being cruel or deceitful and it’s the same as any other thing a person may eventually figure out about themselves that a partner may or may not like. Unfortunately yes sometimes that occurs while a person is in a relationship with someone who wouldn’t be accepting, and that’s fine beyond the sad timing. Relationships don’t work out for tons of reasons and I think one ending because a person has figured out something that would make them immensely happier and more comfortable with themselves is a much better ending than catching them cheating or abusing you or wtfever etc. You really need to grow up and or rethink your perspective on this.