Trans sibling

I'm not posting this because I'm hateful, prejudice, or trying to be mean. I don't know very much about this stuff and if what I say is not politically correct, I apologize in advance. 
I'm truly confused and would like some insight. 
I have a brother- he was born male- that has come out as being transgender. He came out around 10 years ago to his immediate family, but only within the last year has experimented openly. He's always had a lot of emotional problems, including heroin addiction among other things, and I've struggled with his gender confusion because I always looked at it as a cry for help. I'm a Christian, and have been baptized into Christ. In no way am I perfect, and I know that, and I'm not trying to judge. But I have a different opinion about these things, because I don't believe God makes mistakes. I also don't believe in being hateful to people, especially those that are struggling. Jesus loved on the misfits more than just about anyone else in the Bible, and I believe Christians are called to love on people with struggles. So my brother posted today that he will no longer go by his male name. He said that anyone who can't immediately accept him as a female and refer to him as "she" or by his female name will be removed from his life. 
And this is where I am struggling. I love my brother. I have rescued him countless times from suicide attempts, have found him help for his addictions, found him homes when he was homeless, loaned him money to pay his bills, helped with credit and legal   problems. I have done so much trying to help him live a healthy life, male or female. So this post saying that anyone unable to immediately accept him stings. Because I need to be true to myself too. I have reservations about all of this- he's changed his name yet his profile picture is him with a beard. He stole my clothes- including my underwear- since I was 7 years old- which is very violating. He's taken money from me and never paid me back. He still abuses drugs. So now I feel like anything I say puts me in a position to be thrown from his life. 
I know a lot of people won't agree with my faith. And that really isn't the problem. I would love to hear what you would say in response. 
If you are trans, what is your opinion on all of this? Is it normal for someone with preferences like his to have so many issues in life? What was helpful to you when you transitioned?
I love my brother. I don't want to do damage to his life. Any advice is much appreciated. 
Edit: my sibling has faded in and out of wanting to transition. He (I am using he right now because I am struggling to wrap my head around all of this and need time even though it's been ten years) has had girlfriends and lived as a male with them, has had a beard for about 2 years, and regularly goes out with the guys. He didn't talk about it much, and I have talked to him about a lot over the years. It's not that I don't respect him, but it was sudden. He really gave no indication in around 6 years that he wanted to transition. Maybe it shouldn't come as a shock but it does.