A lot of the times trans people may or may not tell their S/O, close family and or friends who are supportive, mainly because they cannot explain their dysphoria. A lot of the times trans people can't put into words how they feel, how they act, how they see themselves. Gender dysphoria in lamens terms is "having an intense desire to change oneself through a series of medication and/or medical procedures to be viewed as the opposite gender, despite the gender expression." How wrong it may feel to have the wrong body parts, or how they look at themselves in the mirror, even down to the clothes they wear or the sound of their own voice. Especially those intrusive thoughts they have when their inner thoughts get the best of them. Sometimes they may not feel that they look like the person they're supposed to be. Often times they are their own worst enemy when it comes to criticism.
Dysphoria is the discomfort of everything that you see inside and outside of yourself and feel completely wrong. No, I'm not talking about "I need to lose weight because I feel skinny" kind of thing I'm talking about feelings that you can't really fix unless it involves some sort of medical procedure or medication kind of thing. You can't explain, no matter how I try, I can only give a glimpse of what it feels like. Plus my experience is not the same as anyone else's. Everyone's version of gender dysphoria is going to be different, and there are so many levels of severity for it, but it doesn't mean it's any less valid. Not everyone will have the same level of gender dysphoria. It may worsen over time, it may get better or it may just vary. It can distort your functionality in everyday life. It can interfere with the way you work, because of the treatment you are receiving due to trying to live as your authentic self. It's hard when society views anyone who's different or who's changing as an outcast. Gender dysphoria is not the same as homosexuality. Your internal sense of your gender is not the same as your sexual orientation.
One of the only ways to relieve this kind of discomfort is the medication called "Hormones replacement therapy" which allows you to take the hormones of the opposite gender to make you appear more aligned to the identity you've been conflicting about. It may not relieve it all, but it can help bring back functionality in your life. It may improve your anxiety and depression, allowing you to live with it in a tolerable state, without it interfering with your day to day lives. Surgeries is also an option a lot of trans people take in order to make themselves look the way they envisioned. Imagining having an internal conflict in your mind and body every single minute, of every single day of your life. Knowing that no matter what you try to do to "correct" yourself you can't. No matter what you wear, you will never feel comfortable or even content with yourself. Even hearing the sound of your own voice brings great discomfort. The very being of your identity brings your so much discomfort that it can result to severe anxiety, depression and even suicidal thoughts. All because you can't seem to figure out how to relieve this dysphoria, make it smaller, make it more tolerable. This is the reality most trans people face every day.