If anyone really cares:
Intersex is a word which refers to a range of conditions in which a person is born with reproductive or sexual anatomy which doesn't quite fit the expected 'norms' of male and female. If there are obvious physical differences i.e. genitalia do not look exactly what doctors expect of male or female or is a mixture of both, intersex people may be operated on very soon after birth in order to make them fit into a 'typical' male or female category. This has historically caused a great deal of distress as people have basically had their genitals mutilated without consent. Intersex people who have had surgery at a very young age may not be able to experience full sexual function as adults because of the surgery. They have often been told nothing about what occurred. Surgical decisions are usually taken based purely on what is easiest to do - for example removing a big clitoris to make genitals look more typically female. This has nothing to do with what gender the person may feel themselves to be as an adult. These things are done to make parents and medical staff feel like everything is 'normal' and as if they know what kind of child they are raising. Regardless of how people are raised and whether they have had surgery or not, intersex people develop a sense of their own gender just the same as anyone does. As adults they may feel themselves to be more male, more female, both or neither. If the difference is internal, i.e. reproductive organs, this might not be discovered until puberty or until someone tries to have children, or it may never be known at all. In reality, human anatomy is far more varied than you might think.
Trans people are an entirely different matter, although there are some commonalities. Trans people do not generally have reproductive or sexual anatomy that is any different from the perceived norm. As babies they are assigned a sex, as we all are, but as they grow up they feel an intense discomfort called gender dysphoria. This is an extremely distressing feeling that can lead to self harm and suicide. The only known effective treatment or solution is to live as the gender they feel they are inside. This may require hormone therapy and surgery. Some trans people aim to 'pass' as the target gender - i.e. to fit in perfectly as male or female without anyone recognising their trans history. This is quite understandable as being known as a trans person can put people at risk from violence and discrimination. Other trans people may choose to live openly as a trans person or are not able to pass.
Non-binary people have gender identities outside male and female regardless of what sex they were assigned at birth. Some trans people are non-binary and some intersex people are non-binary but by no means all.
In response to the OP, I think this is a pretty complicated question. No one is obligated to tell every potential partner every personal detail about themselves. When and how you want to tell people about your baggage, whatever it is, is up to you. Having said that, if I'm in a serious relationship with someone I do expect honesty about major issues.
