I didn't start lifting weights until my 40s. I now realize how great strength is in so many ways.
"No man has the right to be an amateur in the matter of physical training. It is a shame for a man to grow old without seeing the beauty and strength of which his body is capable." - Socrates
Unfortunately, she only goes when I go, and she's retiring in seven months. I don't know if she's going to stick with it when she leaves. I hope she does, as she's been making some great progress.
It's lovely that you got her into exercise, when she leaves you could still arrange to meet her at the gym for workouts assuming she doesn't live miles from the gym, retiring can be a nasty shock for lots of people since they go from full days to "what the fuck do I now" in a weekend.
Also, I've noticed that people in the gym are somewhat narcissistic, so perhaps the benefits are only for this group?
Why is it so great? The control over your body. The feeling awesome and powerful. It has made my life a whole lot less stressful as well, even though I do more.
If you don't have some kind of total physical exertion in your life I highly recommend getting one.
To start, do three things.
Find a bouldering wall. Get a hold of some climbing shoes. Watch videos 5, 6, 7 of Climbing for Beginners [0].
Don't spend a lot on shoes, you will wreck them really quickly and you will certainly buy the wrong sizing when you start.
Boulder a bit and have fun. I enjoy bouldering with a friend the most as it really challenges me. Bouldering walls are often full of really cool and helpful people.
If you like it then watch some more videos to improve technique, think about what you are doing and practice. Consider trying rope climbing (you will want to take a short intro course for this, the rope skills are important).
Then you will start watching super cool videos [1], find yourself at the wall waay too often, and be more interested in finding out somebodies beta than their name.
[0] https://www.youtube.com/watch?v=jbIDnMmSLsc&index=5&list=PL-...
I'm not even referring to just being able to lift something, because plenty of larger framed people can do that. I remember the first time I realized I was no longer "big" came when I squeezed through a thin pathway in my closet. Last week, I ended up doing 7 chained backflips at a trampoline park. What was the point of both incidents? "To see if I could".
If you do some forms of training, you can become very flexible. If you are martial art minded, you can find yourself very disciplined.
Finally, you do get more confident (what someone might see as narcissist or how someone might manifest it).
A CrossFit instructor I know says the best reason to squat is that you will be able to go to the toilet unassisted when you are 80...
I'd love to do it again, but I can't see how I'd ever justify the decision. Luckily swimming, running, yoga are all just as fun.
That aside, most other lifts are fine. The only other one I would suggest people avoid is bench pressing with the smith rack (that's the rack where the bar is fixed and only moves on the vertical dimension). You'll get weightlifter's shoulder from doing that. Stick to dumbbells.
I still dislike paying as much as I do though.