So, who do you think would have been good enough for her? Nobody? You? Or someone like you?
Why didn’t you want her to be with another guy? Don’t you think that reflects your jealousy and possessiveness? If you liked her only as a friend or brother…then as a friend or brother you’d want her to eventually find a nice guy. But since you didn’t even want her to be with any other guy…don’t you think that might indicate you have romantic feelings for her?
After all that you’ve shared, it’s unreasonable and even a bit ridiculous for you to be “clueless”