Here's my immediate thoughts (from personal experience similar to yours):
1. Stress is ANYTHING, good or bad, that gets you excited (or depressed). So eustress is good stress, which most people forget about. It acts just like bad stress, destress, in the way it taxes your mind and body - elevating blood pressure, tensing muscles sometimes, changes in sleep and eating habits, etc. So broaden your perspective on stress.
2. Relaxing yourself is easier said than done. If you are already tense, having problems falling asleep, etc. then perhaps you need more help right now learning how to cue yourself to relax, loosen your muscles, etc. (My husband also thought I should just "think relaxing thoughts", but my body was already tense, causing pain/discomfort so I need to help my body relax, unknot, etc. before I could just relax my mind and body. Think of it like telling someone with the "stomach" flu, just don't think about it and have a big turkey dinner and you'll be fine.)
So take your PTs advice. View the massage as a "medical necessity", not a luxury, until your body is healed and you're out of therapy. Then maybe after you're healed you can try something relaxing JUST FOR YOU monthly - a massage, facial, yoga, etc.
3. I think we all need some time EVERY DAY to relax. Maybe it's as simple as reading before you go to bed, taking a bubble bath, going for a walk after lunch, etc. For some people, they need quiet to settle down their minds. Other people thrive off of exercise to clear their head and make their bodies physically tired. Some are a combo. Find things that help you to relax everyday. At night, make sure you "cue" your body for sleep about 2 hrs before bed. Turn down lights, volume/noises, have a routine for the last hour before bed - get on pjs, brush teeth, get settled into a comfy chair, read, then go to bed. It sounds silly, but our bodies can't just fall asleep in an instant, we need to turn off the TVs and other lights/noises to calm ourselves down.
4. Make sure that you have some "off time" for yourself every week. You need to be able to get out of "Mommy mode", "wife mode", "employee", "cooker/cleaner", etc. We all know being a mom is a 24/7 job. But I keep relearning, that being able to just be ME for a couple of hours every week, is critical to being able to decompress. I love my family, but I need some time to not BE anything for a little while except myself (remember that college girl who hardly had a care in the world?), get dinner for myself (that's not chicken nuggets), girl talking, maybe shop FOR ME without kids in tow, etc. Just being able to "check out" of life for a little while helps me to reconnect at home with a fresh, open mind.
I think many of us have a hard time spending money on ourselves thinking we're being selfish. I've really come to believe that it's just as important for us - physically and mentally - to once in awhile, just have a selfish moment. Then we don't always feel like we're ON.
If you don't have the money to spend on yourself, find some other girlfriends who just want to get together. Play Bunco, watch "chick flicks", scrapbook, etc. It doesn't have to be an expensive affair. It just has to be all about YOU for a few hours.
I think if you implement some of these ideas it will help you get back to your old self. Just remember that your body is a machine. You can't just keep taxing it daily without having it break down occasionally. If you do some "daily maintenance" for it, then the break downs will be less severe in the future. Learn to listen to your body - that means some nights go to bed at 8:30pm, some days eat more fruits and veggies, and some days, kick back and have two pieces of cheesecake!
Best wishes!