It may be that you're having good days and bad days, and it's very hard for anyone else to understand fully what that's like. This may be hard to express, but it's worth trying to let others know.

People usually ask “How are you doing?" out of habit or courtesy. When they ask this, feel free to tell them. Your response may stop conversation or it may pave the way for further discussion. Unfortunately some people can be very uncomfortable talking about your wife's illness and how you are doing. At least you’re making them aware of what your life is like. Some people genuinely want to know how you’re doing. Your answer may lead to more discussion and perhaps support. Either way you're being true to yourself and not hiding your feelings. You may be surprised at how many people are relieved to have you talk about your struggle and how you’re feeling.

People on the other side of the conversation also find it hard to know what to say. Usually they're afraid of saying the wrong thing and upsetting a friend. Honesty from the outset helps both of you past this first awkwardness, and everyone feels relieved that it’s okay to talk about your wife instead of pretending that everything's fine.

Remember that your situation is difficult. It’s natural not to know how to deal with everything around you, including talking to others. Think of your honesty as opening a door. People can choose to enter or not. At least you’ve opened the door and invited them in, instead of keeping it closed and never knowing what might have been on the other side.