Skinny Vs Healthy

I'm blessed.
Other than a few months in college, my weight has fluctuated within the same 7 pound range all my adult life.  Go ahead, hate me. 
I'm only saying this because while I have been the same number on the scale for oh so many years, it doesn't mean I've looked good, felt good or been healthy whatsoever. 
I admire people who take their health seriously.  Because I've been lucky, I'm jumping on the health bandwagon a bit later in life than I'd like to admit.  I finally got clearance to work out in January (within reason) and I'll admit that getting back in shape is harder than I thought it would be. 
I have never been so unhappy with my body as I am now.  Yes, I'm thin.  Yes, it could be worse.  I'm not saying I'm fat.  I'm saying that I'm not happy with the way my body looks.  There IS a difference!  I'm currently working out 2-4 times a week (depending on my back) and obviously, that's not enough.  While I've always been lucky to be able to eat what I've wanted, I've noticed a few things as I've gotten older. 
My energy levels depend on what I eat.
My metabolism is all over the place because of my eating habits.
If I don't get at least 7 hours of sleep, I'm absolutely exhausted the next day.
I'm 31.  And way too young to have any problems like this.  I always thought I'd be one of the lucky ones to get better with age.  For the very first time, I'm GRATEFUL for my injury because it's teaching me that no matter what the circumstances, I'm human and I need to take care of myself.
Point being: I can only work out 3-4 times a week and I have pretty strict limitations on what I can do.  Some would push those, I will not.  So my only option to being as healthy as I'd like to be is to eat better.  I'm good at eating lean and whatnot but there is just SO MUCH information out there on how to eat the best way possible.  I'm not a super disciplined person.  And with my job, I don't have a lot of time at home during the week.  If go to work and then workout, I get home at 8:30 at night, which is way too late to eat dinner or prepare any meal for that matter.  I will never give up Diet Coke or wine.  Balance is my enemy Monday-Friday.  To make up for my shortcomings, I do increase my water intake, I will eat more small meals daily and I might possibly consider chugging a green juice for dinner if it means I'll get the protein and vitamins I need for a balanced diet.
Do ya'll have anything you swear by to be in your best form?  I've started following a few health blogs (they're in my blog list on the right) that I'm hoping will help me adapt a healthier lifestyle.  I'm interested in juicing but am TERRIFIED of the way a spinach, celery, apple, and mint juice will taste. (If it's not good, I won't drink it.  I'm a snob like that.)
If you have anything that will make me a healthier me, I'd appreciate it!  Please share!!

PS-Completely off subject but we may have had a Lucy sighting today.  PLEASE PRAY!  I hate that there are so many stray dogs out there that could be her.  Dogs deserve a home, end of story.  Please pray we get Lucy and her friends off the street soon!