I still struggle with "male or female" boxes as well... I oftentimes have to double-take, because I'm so used to clicking the "female" box, that clicking the "male" box seems strange. Similar to how I'm still getting used to being referred to with masculine language...simply because I'm so...NOT used to it... You know?
Either way, I can assure you that it does get better with time. It's not just everyone else who has to get used to the change - your brain does too. Your brain would have been trained over your entire life to, for example, click "female", and it does take some getting used to...so, yeah.