Death is part of life. It's a part that generally people don't want to talk about, but it's an inevitable outcome for everyone. It's sad and we often wish we could have more time with our loved ones. But the most important thing that they can do for your dad right now is to keep him comfortable. His heart is failing, his brain is not getting enough oxygen, and he can't be the person you knew anymore. You can still be with him, talk to him, he will know that you are there. But he won't be able to communicate with you anymore. It's not because of the meds, it's because his body is shutting down. Hospice is a great resource, they will have grief counselors that you can talk to, and they can also tell you what you can expect with his condition. I suggest you speak with them.