Lonely Lonely Loneliness

I care a little less each day.  Does anyone realize how hard it is to put on a smile day after day and try to be happy, try to stay positive only to realize you are pretending?  Then to hope that if you pretend long enough you will finally convince yourself you are happy?
I am tired or trying... tired of pretending.  Tired of trying to spend quality time with a partner who does not seem interested in building a relationship.  Tired of trying to build a life with memories only to realize that I am the only one wanting to create memories.  Tired of trying to not let this get me down and go out, only to realize all my friends are happily married with families and dont have time to go out.
I feel like I am going to be creating a life all by myself.  I am not a defeatist.  I dont give in or give up easily, but I just get to tired of trying to build a meaningful life and trying to find someone to enjoy it with me only to realize no one is there.
I know the saying, happiness can only be found with in.  I need a break... I guess I need to withdraw from people for a while because there is something wrong with being surrounded by people and being completely and utterly alone (or at least feeling that way).
I guess I need to learn how to be my own company and to be happy with that.