Need advice

I am married to an epileptic. She has only had 4 grand mal seizures in the past 10 years. She is on only Lamictal at this point to control epilepsy. She is also on thyroid pills to regulate her low thyroid, and has had a pituitary tumor, and is sensitive to gluten- and has severe endometriosis. On top of that, she has a lot of side effects and mood disorder at this point that she is unable to tackle, or admit or figure out what to do about. My main issue at this point is that we have not let her illnesses stop our living. We are just barely in our 30's and have enjoyed many things that life offers for 20 yr olds... we have a family of 3 daughters, and have made it through 3 rough pregnancies and 4 miscarriages... She has started a business as a dance studio owner/instructor this past year. She ran a marathon... She feels invincible. I am REALLY struggling. I feel often like I'm not married to the person I first met 12 years ago. I love her still, and love who she is/was... it's just that the side effects of medicines and illnesses have really caused a huge switch in her. She used to be very able to handle life. Now she's confused. Now she is often sad. She is really really really tired all the time. Sometimes to the point of not being able to walk well. She can't always keep the same function in terms of speech. She slurs words and forgets phrases. To the general public, this is totally not noticeable. She makes it work... she talks of being tired. People don't realize how bad it's becoming. Even she doesn't. Also, she get very angry quite often. She lashes out on our kids (not physically), and it's beginning to be hard for them to recognize why mom is that way. I feel like I'm taking a beating emotionally and I'm not strong enough to handle the whole burden of my wife's health and my own subsequent depression stemming from both hormonal imbalance and situational issues. My wife is not who she was before. I want to understand her- but I feel so often that it's beyond her control... that she can't fix it and doctors don't understand it- and MORE medicine and more tests are not going to fix it... This chronic never-endingness of worsening trials is hard. and we're only in our early 30's. I wonder what happens when we get old and our bodies really give up on us. I guess I don't have a real question here- just feeling very alone and with nobody who "gets" me. People expect that with any illness that it will get better. That's always the assumption at 30. My closest friends who do understand epilepsy even don't understand the chronic issues it can cause- and the fact that it's not going to get better just because time has passed. I feel very very alone and very sad that even my wife doesn't see how much things are changing and how hard it is for me to cope with it all. She just gets angry and over emotional at everything. Sigh.