Kestrell wrote:I'm writing this in kinda a bad mood so sorry in advance...
Quinn is moving back in with his owner at the end of the month. He is old and has been slowly getting lame and just has had a bad last couple of months due to abcesses and lameness issues. We found out today that both suspensory ligaments are causing him pain... He is officially retired now

He meant so much to me and helped to get rid of a lot of anxiety that I had and he taught me so much over the past year of having him... I guess I'm wondering how you guys got over loosing a horse?
I'm sorry to hear about this. It is always difficult watching a loved animal grow old. I don't know how useful this will be to you, but here goes.
Firstly, are there any practical steps you can take to make the parting less painful? For example can you arrange to stay in contact with his owner and visit him? Can you maximise the time you spend with him for the remainder of the month so you part feeling you don't owe each other anything? I haven't been in your situation exactly, but I have exercised a couple of ponies for other people and then they have been sold or I have had to stop for other reasons, and in both cases I felt that I hadn't done enough with them while I had the time. If you feel at all like this, there is still time. I'm assuming he's not sound to ride but you can still hang out with him, lengthy grooming sessions etc. It really does help if you can feel you did the best for him. Which leads on to the next point.
Treasure your memories with him. You said he helped you with anxiety and he sounds like a horse well worth honouring. It can be really helpful to write about your experiences together, or draw or make photo collages or whatever appeals to you.
Lastly, it's ok to feel heartbroken. It's ok if you are so upset you can't even bear to think about him for a while until time heals things, and it's also ok to feel much less upset than you expected to, or to be anywhere in the middle. Whatever you feel is valid and you shouldn't be under any compulsion to "get over it."