What CHF treatments will not cause fatigue and memory loss? My mother's apparent "dementia" arose from lopressor (metoprolol tartrate) when she got CHF after bowel surgery.

Avoid betablockers. CHF can be treated without the use of a beta blocker (lopressor) although using one is preferable. Thus she can be treated with a diuretic, angiotensin inhibitor, aldosterone antagonist and, it might be reasonable to try a different beta blocker such as carvedilol. It's commonly started at an exceptionally low dose (3.125 mg) and gradually increased to 6.25, 12.5 and 25 mg - all twice a day.
Work with doctor. Both CHF and medicines for it can cause fatigue and other brain symptoms. Work with your doctor closely.