Here's what I know...
(1) You are not alone; many people feel like there are very few people who really understand them.
(2) There are people out there that want to have a very deep relationship, you just need to keep on the look out for them and not settle for someone who isn't of your caliber.
(3) It usually takes a person who has had some drama, loss or difficulties in their life to make someone want to have a deeper relationship. If you are dating Mr Happy Go Lucky, it is probably going to be difficult to get him to understand you.
(4) Not everyone is for everyone. You need to find who is right for you, not obsess over who isn't.
(5) You need to make room for the possibility that someone can catch up to you in desiring a deep relationship; you just need to give them the time and the space to try.
(6) You need to be open to understanding someone else's definition of a deep relationship and see if perhaps the two of you can find a happy medium.