Yes, I felt that way just about a month ago. I had a string of animal deaths that seemed like it never ended, and I quit rescuing bettas and taking in other animals because of it. It was really hard to get through it, a lot of crying involved for sure, but eventually I did. I'm actually just starting to rescue bettas again (as of yesterday) so I know it is possible to overcome this difficult situation. Feel free to talk to me about anything going on, or just post it on the forum, because there are a LOT of people who have experienced this and would want to help you through it. :)
Kindness and respect should be shown to all animals, no matter if they are furry, scaly, big, or small. Be a hero to the animals and GO VEGAN!