Why do we always question our happiness?

Why do we always  ask questions and look for a reasons for our happiness?  We often ask ourselves when everything seems to be perfect is it too good to be true? 
I think is possible, actually I know it is because I am living it. Nothing is perfect and nothing is forever but when is reality I except it and I don't ask questions. Why we always get scare more from happiness and joy than from fear and pain. Once you feel happy and find yourself smile for no reason why do you have to ask why. Instead ask yourself WHY NOT? 
You deserve to be happy, to smile and to enjoy life the way is giving to you. You attract what you create. If you create happiness surround you that's what you going to get back. The feeling is just amazing when  you realize that you are above the small problems and answer with positive attitude. You happiness depends on your approach of life. When everything is good in your life don't try to find something or don't try to create the reason not to be, because when you looking for something you will find it but is it that what you are looking for or you are just afraid to face reality. You are saying " This is too good to be true" so does that mean you want to be unhappy, miserable and sad  to be more believable or do you want to enjoy these happy days and look forward for tomorrow? I know maybe is hard to except that is just too good to be true when your girlfriend is Hot, Smart, Hard Worker, Good cook, Love to clean and wash  dishes, Doesn't want any gifts just your love, Tells you everyday I love you and on top of all that she gives you the best blow job ever and always horny for you......TOO GOOD TO BE TRUE. Well yes I can see why you are afraid because is too much of a good but how about if you don't look for any reasons and stop question why is so good . Don't be afraid to be happy and to be loved. 
You have a reason to smile and once you make it a habit there is nothing that can make you cry. Keep your face to the sunshine and you cannot see the shadows. Is just so simple don't make it complicated. Don't think about if one day will be over think about how can you keep it longer. If it seems too good to be true, it probably is.