The only couple on this list who actually hooked up prior to the series ever starting, Grey's Anatomy kicked off the morning after Meredith and Derek went home from a bar together. Sure, he was married at the time - but that technicality was no match in the end for (sorry we have to say it...) the McDreamiest pairing on all of television.
Vulnerability isn't the opposite of strength. It's a necessary part. You have to force yourselves to open up, to expose ourselves, to offer everything we have and just pray that it's good enough. Otherwise, we'll never succeed.