<human>: Can you provide a brief overview of the text?

I have been with my GF for over 7 years, and the excitement has obviously been going down over the years. Lately though, I have actually been feeling more and more down about our relationship. 

She has been gaining weight for a while(Nothing too serious, but it is definitely showing now) and we have talked about this before, but no major changes have been made. she knows how important the physical part of our relationship is to me but has never taken initiative or seriously tried to improve her body (for longer then 3 months)

I feel like I am missing out on an important part of my life, and when I see a young healthy couple I cannot help but feel a pang. On the other hand we have been together for a loong time (for my age) and I feel like I will never meet someone who knows so much about me, and is accepting of all my flaws and behavior.

I have serious problems with this, and cannot decide where to go next. I don't wanna make too many long term plans but am too afraid to take the next step to improve or end the relationship. We talk a lot and are educated, and we have a lot of things in common, but I sometimes lay awake at night being angry over the lack of physical spark and initiation from her side.

Where do I go with this?
<bot>: I am not physically attracted to my GF anymore, but I fear for ending up alone. Any advice to get the spice back or move on?