Most often it's our belief about 'what is' that is the problem -
beliefs we insist on holding & defending without question.
How often do you do things robotically, without any consideration or forethought, simply by rote? We are such creatures of habit that it is not uncommon for us to be asked to explain how a certain process is done and not be able to come up with an answer, even though we do it constantly. We don't pay any attention to what we are doing, it's simply habitual repetition.
This is how our belief system works... Belief: an acceptance that a statement is true or that something exists.
Your beliefs have been stockpiled since childhood from various sources, parents, teachers, culture, religion etc. and you have always automatically reacted to certain situations, in the same manner. The mind just refuses to go anywhere else. You believe what you are doing or saying, without ever having questioned or examined it. Until you are in a situation that rocks your world, you may never take a look as to why you do what you do.
It is certainly time to take a look at why you are missing out on so many things in life. Are you running some old record of beliefs that is no longer valid for your life? You need to take a look at all your belief system and question each and every one of them. Figure out which to keep and which to kick to the curb, you will feel a gigantic sense of relief when you do.
It is not necessary to miss out on anything in this lifetime. The only one stopping you is you.