I just lost my mom two weeks ago and I did give a eulogy. I figure I would be good at answering this as I just went through it.
For me, it was a strange day in general. There were parts that were hard and parts that weren’t when it came to the eulogy. My goal was to get through it without completely breaking down, and I almost almost did that. I actually did ok with most of it but when I got to the part where I described how incredible my dad was and how much my mom loved him, I lost it. I just felt so horrible for him.
Personally, I couldn’t write mine until super last minute. We knew she was dying but I just couldn’t write about her before it was real. I also felt like I didn’t have the strength but I knew it was important and something I would regret if I didn’t do. it was definitely exhausting but heck, this whole thing is.
I truly truly hope your parents stay well. Enjoy what time you have and try not to worry about this stuff until/if it comes!