I wouldn't take the take the unwillingness to discuss his feelings as a rejection of you specifically. Even when they love and care for each other deeply there can be some allowed space between people. I was in a sort of similar situation a few months ago, where there was some sort of big dramatic dustup between all of my friends. So naturally, being deeply enamoured of my friends and wanting them all to be together and happy as they had been in the past, I tried to be a sort of mediator even though I wasn't really aware of anything that happened (I don't know to this day) I assumed that I had the power to fix whatever problems there were. And my best friend, when I brought it to her, told me very bluntly that it was none of my business.
And she was right, really. My relationship with her, close as it was, did not give me license to pry into her affairs. I had no right to confront her about whatever happened, I was in no position to make demands or even be of comfort, and even though I had good intentions I would've ended up causing more grief had I made an issue of it. But we're still friends and we love each other very much. The thing is that because you're friends you can't assume that he needs you to get through his trials, even if you need him to get through yours. If he doesn't want to speak of whatever is bothering him he has that right and you ought to respect that. But you can put it on the table that if he needs to talk to someone you are always available.
As for the blog, well, don't take it so hard. Don't assume that you're on the outside of his life because of this thing. Again going back to my situation, my best friend keeps things from me, I know she does, and there are people that she is more open with than she is with me. But she's only known me 2 years now, and what's more, she has never been dishonest with me. Withholding information is not dishonest and it's not meant as a slight against our friendship or her view of me. Honestly you really shouldn't define friendship as requiring being 100% open and honest about everything with you, that is a very difficult thing to ask of someone. A lot of us here disclose a lot more online than we do in person, and just because my brother might not know things about me that Johnny C does doesn't mean I value Johnny C more than I value my brother. I tell my therapist everything and my dad very little about my internal life. I don't think that's really a bad thing. Honestly you went snooping and it's unfair for you to hold this blog and its contents as something he's been intentionally obscuring from you because of you. I doubt when he decides he really wants to be friends with someone he gives them a link to the blog. Relax. If this guy didn't think well of you he wouldn't be in the position he's in, being protective and caring for you.
And as far as his "you're welcome" reply, I think you might be overanalyzing it. This is something I do a lot when I'm depressed. I'll pore over text messages and emails and think "Is this what they mean? What if they meant it this other way?" but it's not rational.
