If you find yourself with a great person in a relationship is physical attraction still as important?

Ok, so let me clarify. If you find a person who has a great personality, really sweet, treats you well, shares your core beliefs but you are not always so physically attracted to that person is the relationship a no go? I just want to be sure I am not being too shallow. Further more what if you are already in the relationship but just started to lose that attraction….. Thoughts?