<human>: **Back Story:** 
I am starting to feel the honeymoon phase slowly come to an end with my boyfriend of 11 months. The reason this concerns me is because I have never made it past the honeymoon phase in a relationship. Previously, I have been in 2 long term relationships and always end up breaking up with my SO after a year or so because I find myself less attracted to them, less interested in sex, and bored in the relationship. 

That being said, my current relationship is much better than any past relationship I've ever had. After 11 months, I still genuinely enjoy being around him. I am still very attracted to him, and we always communicate everything so well. We have a lot of the same views and opinions. He puts a lot of effort into the relationship and there has never been a day where he has made me sad. These reasons are why I want to keep this man in my life. 

**The Problem:**
However, I believe the honeymoon phase is ending because I find the excitement is gone. Which is making me question my feelings - not seriously, but sometimes I will catch myself thinking "what if I were dating someone else?".  I find myself missing the excitement of meeting a new person. I also find myself less interested in sex as I was in the first few months of the relationship - although I am still very attracted to him. This might sound childish to some, but for a young person trying to find peace with being in a long term relationship, these thoughts concern me.

I do know that I have very strong feelings for my SO, but I'd like to know if these are legitimate problems as opposed to the natural progression of the relationship.

Can you summarize the given text in a few sentences?
<bot>: The honeymoon phase of my relationship is ending. How do you learn to love your SO in a new way? A way without excitement but still whole heartedly?