I have a pacemaker and I was feeling better by week 6. Everyone is different and sometiems pacemaker settings need to be adjusted. As with anything, it will take getting use to. Talk things over with her doctor...look at medications she is taking and how her activity level is. This will help her physician understand perhaps where she is coming from. I've had my pacer for 4 years and am 25 years old and my first year my pacemaker had to be readjusted to many different settings before I was comfortable. Best of luck and remember the physician doesn't "know" how the patient feels...unless of course they have a pacer. Having one and placing one are two different things. Be good to your heart and it will be good to you.
~Ode