Sometimes you need to confront your adult children because their actions or attitudes are self-destructive or not beneficial to the well-being of the family in general. Before you confront the adult child, it's important that you have your facts straight because you don't want to accuse her of doing something when maybe it was a misunderstanding on your part. You also don't want to belittle the person's character because it will make the problem worse.
Let your adult child give his side of the story. If you believe that he doesn't have a strong work ethic because he tends to get fired often from his jobs, let him explain the details of his work situation. Maybe he was laid off due to company decisions and it wasn't his fault that he lost some of those jobs.
Focus on the main issue at hand. If your daughter feels that your careless spending habits are causing you to struggle with paying bills and rent, don't get defensive by talking about her financial habits. Instead, think about what she's saying and examine your habits regarding money to determine whether she has a valid point.
Handle the confrontation in private. Meet with your adult child in another room of the house or outside in the backyard with the door closed, so younger children can't hear what you're discussing, especially if it's a serious issue. Also don't bring other adult relatives into your confrontation unless it's necessary because this will make the adult child feel like you're attacking him personally.
Figure out solutions to the problem. If your adult children seem to be ungrateful for things you've done for them and instead they complain about what you didn't do for them, ask them why do they feel this way and to give you specific incidents where they felt you weren't there for them. If you find that some of those examples are valid, apologize and ask them how you can improve the relationship from this day forward.