The point of all this, however, has not just to provide information & make you feel depressed yourself, The main point is that many of thses difficulties can be overcome or dealt with. One of the best things my Dr (and yes, I mean an MD) ever did for me was to put me on to Ginko Biloba. This increases the oxgen levels to the brain & elsewhere in the body, and as such greatly increased my memory function. I am probably still a bit more absent minded than most, but I fit within the realms of normal functioning now. In addition my ability to think logically and clearly has returned. I never knew just how much I had lost, until I got it back again. This also helped to reduce the lethargy & physical exhaustion to a point where I was able to resume normal physical activity. But I wont ever forget what it was like to walk the short slope to my house "one step at a time" never knowing if I would have the energy for the next.
Another thing I would Recomend is st Johns wort. It is a mild anti depressant & can be bought over the counter here, although I know it is a prescription only medicine in some european countries, but if you can get it then do. It functions in the same manner as the tri-cyclic anti-depressants but is much gentler on the body and will not interact with whatever anti epileptics she is on.
Of course one of the obvious necessities to help her overcome this depression (& therefore the insomnia) is all the support and encouragement her family and friends can give her and the Dr's will waffle this off to you as if it's some sort of 'Happy suit' you put on each morning. But it's not, it is hard and it is stressfull as you quite obviously know. Trying to adjust to the changes in her behaviour on a day by day, hour by hour basis while being supportive stretches you to the limit, and all the while you are also having to deal with the shock and grief of dealing with such a thing happening to someone you love. Here is where it is vital to look after yourselves, especially so for your father who you say is very stressed. Make sure that you make time for yourselves to do things that you enjoy & cut yourselves plenty of slack, punishing yourselves for your mistakes achieves nothing but to drain you more. And always remember that it is not your fault, that may sound silly but it took my mother years to stop feeling guilty for my having epilepsy. Another form of what the shrinks will call "survivor guilt".
Learning to live with epilepsy and with someone who is epileptic is mostly a process of adaptation, there are lots & lots of little techniques & coping mechanisms that you will all develop, as you go along, to live with the situation, but it won't happen quickly. All that I can offer is that it won't be forever. It's just one step at a time.
Also, it may seem obvious but let your mother sleep-in in the mornings if she can & if it is possible. The notion that getting up early will somehow help her get to sleep early does not apply here & she is not being lazy. Although I expect you've figured this one out already it is still worth mentioning.