Moonpie,
You are absolutely not a bad person for feeling like you do. Something normal, such as a love and communication of your family has been disrupted, and it takes time to come to terms with it. I don't think it will ever truly make sense, but you can make peace with it. There are so many people here that even though intellectually they understand the terms of KH and WTS, it is heartbreaking when their own parents and siblings will not acknowledge them.
I was DFd 18 years ago. For the most part, I didn't truly suffer the loss of my family's involvement. I did however lose privileges of family dinners, anniversaries and such. When both my grandparents had huge 50th Wedding Anniversaries, I was not invited, it slightly hurt because of course everyone talked about it for years.
But through meditation and realization of my life, I made peace with the facets of imperfection that exist, things I can not change, I have accepted and the truth is I haven't been happier. I could beat myself up over it, or I could learn to deal with the life I was given, in all its imperfections.
I think going through the process is good, there are people that have wrote letters and mailed them, as a way to deal with it, and then moved on. Sometimes even writing a letter that you may never send, but just to get out your pain and hurt may help, having a good cry and then being with friends that truly love and support you helps. I think this board is a wonderful place to share such things and make peace with it in the process.