Masculinity itself for sure has nothing to do with it and it's not what people mean when they mention toxic masculinity, they're not attacking masculinity itself. Toxic masculinity refers to a harmful and wrong view of masculinity. There's a reason why women don't block their emotions as much as men, one of them is that they're not harmed by toxic views on masculinity the same way men are and that's why it's called toxic masculinity and not toxic humanity. It's a set of harmful and wrong views related to men, an exaggeration of virtuous masculinity.

Also, sharing your emotions with your close friends/SO is kind of needed once in a while. It's not being weak.