I am hoping you did not put your brother up to that text. I know I sure did silly things like that. That is controlling and manipulative and not working on yourself. I would ask your family to stay out of your private personal matters. If you want to continue to push him further away continue to allow that stuff to happen. Trust me on that.
As far as your secret plans only you know your sitch and what is working.
As far as the apology you probably should have just ack'd it and left it at that. Thanks, I am doing the best I can. The last part you threw it in his face a little.
You are projecting and overanalyzing this below. Sounds like this is a 180 for you below and he is ack'ing it. Good. 95% of your anxiety thoughts are wrong. You here that. 95% of your anxiety ridden thoughts are wrong. I struggle with that still. But in the end during my entire sitch I was always wrong. I remember one incident she wrote an address on the fridge whiteboard. I thought it was apartment for her to move out with kids. I google'd the piss out of it. call my real estate agent. Went crazy. It ended up being a craigslist address to pick up a doll for my daughter.
"He also said something again about the outing on Saturday but it was more on the lines of "I'm glad you are reaching out to connect w old friends and meet some new people." It sounded sincere....which for me hurt b/c it was like hearing "I don't give a $hit if you go out & meet some new guys. It will make me feel better."