My wife of 4.5 years and I are getting divorced, mostly because of my transition. We both thought she married a masculine man, and it turned out to not be the case. There are 3 daughters involved, 2 are mine (4, 2.5) and the oldest is from a prior relationship (10). We are both sad at the divorce, but she wanted to be with someone who is masculine. My wife was actually the one who pointed out I might be trans, by the way, and is completely supportive of me. We are still best friends, and always will be, and we will always love each other, but as a couple, it just wasn't meant to be for us (other reasons than being trans were involved, too).
So, just keep it in mind, just because the marriage may end, doesn't mean that the friendship or love isn't still there. Hopefully you will still be able to remain best friends if you actually do divorce. Just make sure you do what you need to for you, no matter what, or its all for nothing.