Jack - every so often I think all of us get to that point. Maybe you need a break? Do something that you're able to enjoy doing on your own. (just because you're in a loner mood, unless you are comfortable enough to do something with someone)
Also, I try my best not to use the word "normal" ... unless it's to refer to the setting on my dryer. A long time ago I figured out that no one is really "normal" ... there is no definition that can be agreed on!! "Normal" is in the eye of the beholder.
I am sure this will pass ... but in all honesty, do try to do something that will make you feel good. Be it reading, exercise, baking goodies (and eating them guiltlessly!), a long walk, listening to music ... ahhh the list goes on and on