I think the “you’re crazy” stereotyping around going to therapy is so unhelpful (I’m not having a go at you for saying that - if you think it would help you, please don’t be put off by what some people think about it! You don’t even need to have mental health issues to find therapy useful, either). I don’t have a lot of advice for dealing with your family but the way they dismiss you sounds horrible, and unsupportive. Having some kind of coaching perhaps would help you find better ways of getting through to them - although, if it’s because they don’t actually want to listen, you’re probably fighting a losing battle anyway.
Your feelings are valid even if they don’t want to acknowledge them.