I think you're both TA...
Your brother was obviously not ready to get married, should have been honest or gone to counseling and been honest or something. A lot of counselors would recommend being single for a whole year before you pick up with someone else. Like SINGLE, not dates, just fun with friends NOT of the gender you desire. I know it sounds tough, and it is, but some people find by the end of the first year, they tack on another year, knowing they've just begun to deal with the holy-crap-face toxic relationship.
Your brother was obviously not ready to get married, should have been honest or gone to counseling and been honest or something. A lot of counselors would recommend being single for a whole year before you pick up with someone else. Like SINGLE, no dates, just fun with friends NOT of the gender you desire. I know it sounds tough, and it is, but some people find by the end of the first year, they tack on another year, knowing they've just begun to deal with the holy-crap-face toxic relationship.
This book is a must for people like your bro - https://www.amazon.com/Dating-Dummies-Joy-Browne/dp/0470892056
And as for you? I think it's possible you either knowingly or unwittingly became Andy Dick in this situation.