<human>: Can you provide a brief rundown of the text in within 3 sentences?

I am in the relationship with this guy since forever. he is my first and I am his first. when we started dating I did not love him  - he was my best friend and eventhough I told him NO the first time he asked me out, I just could not see him sad so I figured - let's give this thing a try just to let him know that we are not fit for each-other. one thing led to another and we ended up being together for 6 years now. we had our ups and downs but always made it through. In the meantime I think I felt for him. The thing is that he makes me feel good for myself and I enjoy spending time with him, but the more we grow up the more I notice differences between us. I mean to be honest - I am not an easy person to get along with. I can be quite a pain in the ass and he is the only one that gets me and tolerates me even at my worst. 

But lately I have been having second thoughts. what if what we have is not enough? what if the differences can lead to us hating each other later? i have given serious thinking to us breaking up but I always end up with OHH NO we've been together for 6 years and went through so much together. there's no chance I could find another him. 

but then again, it's like lately I don't miss him so much, I can perfectly be on my own for days and not miss him like at all. I don't know what is wrong reddit? what should I do? 

Please help. any advice is welcomed.
<bot>: been in a relationshup for 6 years with a guy I did not initially love. felt in love afterwards and now I am having second thoughts.