Knee pillow, has anyone tried it?

So this is baby #3. 33 weeks. Told my doctor about back pain, and hip pains. Been lucky so far pelvic pains have been minimal. All the doctor said was get massages regularly.... no money and no time. I've been trying to sleep with a pillow between my knees because I read it would help with alignment and had other benefits. But when I turn the pillow gets stuck I end up swearing and the pillow usually ends up on my unsuspecting husbands sleeping head. Cause if I'm not sleeping then he shouldn't be either.... petty I know, but I'm in pain and frustrated and TIRED.

So has anyone tried the knee pillow? Was it helpful?