I'm so sorry Hunter.
My parents had to make that same decision many years ago. My mom bought my dad a Pekingese. Beautiful dog. Brown fur with little streaks of black in it. Well, anyway, as years went by, the dog got really sick. They had to make that same choice. Granted they could've spent thousands keeping the dog alive, but in the end, it was just prolonging the inevitable. So, I had to take the dog to the Vet's and had him put to sleep. I never want to experience that in my life again. I just dropped him off, patted him on the head. Told him everybody loved him and left. I got in the car and just shook. A person isn't mentally and emotionally equipped to deal with that. I know I wasn't.
As for my cat. He was my baby. He had the run of the house. There was only two places off limits to him, the table and the kitchen counter. Other than that, the house was his.
I remember one night not too long after we got him, we decided to have liver and bacon for dinner. Well, we sat down to eat and this cat started meowing like crazy. Turns out, he loved liver and bacon. So, I got a small plate cut a piece of mine, cut his up in smaller pieces and gave him a small serving of bacon and this cat almost inhaled it. We learned after that, next time we have that for dinner, make a little extra for him.
Every once in awhile, he'd jump up onto the back of my chair, lay down, put his head on my shoulder and watch what I was doing on the computer. If he wasn't situated right, he'd put his paw on my cheek and make me move my head a little so he could see. And his tail was always flying in my face. He purred loud too.
Whenever I came home from work and fed him, I'd talk to him just like I was talking to a real person. Every now and then, I'd get a tiny meow. His ears would move back and forth as I just rambled on. As soon as I put his dish down, I didn't exist until he was done. Then, he'd come lay next to me, clean his face and paws and leap up on my lap and curl into a ball of fur and snooze.
As you can tell, I still miss him. But, he's not too far away to visit. I've got pictures, I have a picture of him on a coffee mug. That one is wrapped in plastic and put away. I've got him in my game now. He's never too far away from me, just like when he was alive.
I decorate for fun. I like to try out new and different things just to see how they look. It's a creative outlet for me.
Here's a better picture of the cat:

That's me taking his picture.