I have learned that the Creator and the universe gives us two sets of answers- that which has been made especially for us, and that which can be made by our actions and choices, and that both can be an equal blessing
When life clicks for you, and you finally get it, and understand who you need to be, just be you, and do you without apology.
With the Internet and digital cameras and camera phones the reputation you get right now will follow you til you die and then still live on with your kids and grandkids.
It sounds like you both need to have a heart to heart putting all your issues and fears on the table and then come up with a plan to face them together so that they are no longer obstacles to the future the two of you could so happily have. But you both have to be willing to do it.
Are you being too picky? Who am I to say? We all have a right to say for ourselves what we require to have peace in our lives. Your sibling’s mates may drive you crazy but there is always someone out there who is made to love somebody , even them, and even you.