I'm no Ellen fan but, to be fair, she does warn against "repeatedly" lifting heavy weight. Lifting kids and grocery bags and handbags probably aren't considered as weight lifting, as in repeatedly lifting weights for several reps/sets.
That being said, I have had experience with shoulder pain. The cause? Well, my p.t. said it was due to poor posture. But what exactly was causing the pain? Wasn't it ligaments and/or tendons that were strained from having poor form? And what corrected my poor form? Strength training!! My p.t. started me out with 2 pound weights because I had been avoiding upper body work due to my pain and I was out of shape. But, one year later, I have progressed and I now use five pound weights. But my p.t. gave me no instructions on what weights I should use as I progressed. He didn't tell me to stop at 5 pounds, so I plan to go heavier as soon as I'm able. As long I could do the exercises correctly and as long as they aren't causing me any pain, I can use whatever poundage I want. Having a strong upper back, rear shoulders, and rotator cuffs (while limbering up the chest muscles) seemed to be his goal. And you know what? It worked. Almost one year after my last p.t. session, I am still pain free, all thanks to strength training.
OK, sorry I went a bit off topic.
Donna