Val,
finally a topic I can actually help YOU with! I LOVE to exercise and I'll tell you how I grew to this point.
First of all in your blog you give a lot of reasons you "should" exercise and "should-ing" all over yourself is never motivating. You then say you "feel so good and look better" after you exercise. So you're using it as a means to an end versus a great experience. So here are the steps:
1) Move from a "should" mindset to an "I DESERVE" mindset about exercise.
You have that trainer becauseyou DESERVE to feel and look your best.
You GET TO move today by choice when so many others no longer have that choice.
I think you get the point. Use more DESERVE statements
2) Try to combine what you naturally LOVE with exercising.
For example for me I LOVE certain shows and so in my workout room I have a treadmill and an elliptical and certain shows I ONLY watch while working out.
Try to get to the root of your exercise "style". Are you a group exerciser?(I get annoyed working out with others so this doesn't work for me)
I think you've mentioned you enjoy walking outside but your schedule is like mine in that you're on the road all the time so that's incompatible with your lifestyle.
Do you love music? Then load up and ipod and only listen to your fav music while working out.
Have you tried workout videos? I LOVE workout videos and take them on the road with me. I pretend I'm leading a large group of women through a great class(see I have some actress in me too)
3)Personal trainers are great but don't think that just because that's the 'in' thing to do that you HAVE to have a trainer. There are great home workout videos out there so check them out. I love www.collagevideo.com because you can return the videos within 30 days. I also love the FIRM videos because all of the instructors also have full time jobs.
4) last thing...If you want this to be like brushing your teeth then you make it non-negotiable -most mornings a week you do it! Note I said MORNING because it's the least likely time to have interruptions/excuses.
I workout at 4:30 or 5 most mornings and it's a great way to start on a natural 'high'.
All the BEST!
Hope