One thing you should know is that people can surprise you. I was positive my grandpa (Fox news, voted Republican regardless of views, etc) would just pretend it wasn't happening. A week later, he hugged me and told me he loved me no matter what and never deliberately deadnamed me again. And sometimes the same thing happens over longer periods of time. One of my uncles deliberately deadnamed me for a year, then something clicked and he hasn't used the wrong name since. A guy I worked with misgendered me for a year, then one day suddenly started gendering me correctly and hasn't messed up since. People can surprise you and people can change. As for the dysphoria issues, sports bras can be incredibly helpful for some people, and cutting your hair short doesn't instantly make people think masculine. You can cut your hair short because it makes you feel masculine without anyone knowing the real reason. If they demand one, you can always say it's too much work, it's too hot, etc. Or you can wear your long hair in a more masculine way, since having long hair doesn't equate to femininity. Good luck!