I’m so sorry you went through that, it has to be traumatic. And those flowers will be beautiful.
As for coco, take a deep breath. Were they a bonded pair? Were they separated? Why would you give him up? If he was a bonded pair, you can spend time with him more, he will need a lot of attention if they were a pair, as he can get depressed and not want to eat so for the next 2 weeks he will need to stay with you and you care for him. Going to a new home can stress him out and if there is no reasonable reason to give him up, keep him. And you may realize you want it to be just you and him or you can bond him with a friend.
I understand the pain is so much, I knew after one of mine died I didn’t want my other 3, but he was so sick for months I was emotionally drained but I’m glad I kept mine. We get animals till they die because we want to care for them and it’s till death. They teach us so many things that humans can’t and that’s why it’s important to have animals and going through a death of one is hard but you wouldn’t be who you are if you didn’t have them. So take a couple of weeks while you and him grieve and get a clear head. It’s all too soon to make any decisions and you may make the decision to give him up but again later, wait a couple of weeks until you are mentally clear. He needs you, now and in the future. It’s very hard to loose a bun, and you will go through deaths with animals but we didn’t sign up for a lifelong pet, we know the day is gonna come, and we always need to be understanding and realize nature is going to do what it needs to and even with medicine, it won’t prevent the inevitable. Remember she is always with you, you may not feel it now but she is and take time to grieve, everyone grieves differently and for different periods of time. You can set up a little memorial of her on a table, sometimes it helps people.