desperation

Its bad enough being single and "normal" and having difficulty finding a shidduch but when I hear people talking about their diagnosed mentally ill relatives and how they hope that that will marry I silently lose it. I realize that they don't mean to be inconsiderate, but when they speak about mentally ill people who are not in my opinion capable of taking care of themselves let alone marry but I  lose it. I try to be polite and not spell out my feelings.  I tell them that they should just worry about their loved one being able to take care of themselves and live a happy life . I certainly wouldn't want to date anyone like their loved one and their loved one is too naive and vulnerable to date anyone let alone marry. I try to be polite because I know that people are in denial about mentally ill loved ones. They  know that wishing them marriage is a dream but they can't help themselves. They don't realize that speaking to me about these fears is not the best idea. I feel too stupid about my resentment to confront them with my true feelings on the subject , so we  continue to have this conversation.