Why can't I say no?

I love animals. I currently have 8 cats, 2 dogs, 1 tarantula, and 3 fish tanks with my boyfriend. We live in a small house and really don't make enough money to live on. I know that having all of these animals really doesn't help our situation, but both of us are such animal lovers and we really have a hard time saying no. Actually we did only have 4 cats up until about a week ago. Then the number of cats we had doubled to 8. I am the one who brought the last four home.. First I found these 2 kittens that were about 2-3 weeks in age, and were abandoned in a sewer. I got them out and nursed them back to health. We were going to try and adopt them out, but fell in love with these little boys in the process and decided to keep them. Then while I was on my way home one day, there was an accident on the highway and people had to take gravels around it. I had just got on the gravel when I saw 2 very young cats come limping out of the ditch. I got out of my car to see if they would come to me, they both did and were rubbing against my leg, let me hold them and look at their wounds. They both had huge gashes on them and one had a limp back leg. I put them in my car and they curled up in the car seat and slept until we got home. We had them both fixed and they were both given medical attention for their wounds.  We have them outside in our shop right now, and are trying to decide what we should do. I don't want to get rid of them, because I don't know anyone who would adopt them. I want to keep them, but it really isn't in the budget. I don't know what to do. I cant deny these innocent animals who really have no control over what happens to them. Especially when they are so sweet and loving.  I feel like they are showing their appreciation to me for saving them.  I have never gone looking for animals. All of my cats and dogs have been rescued. Found limping out of the ditch, abandoned at 2 weeks of age, laying on the side of the road, taken from abusive owners, and saved from a nasty dog trying to kill it.  I could never just walk by and let them suffer. I feel like there has to be something that I can do.. My parents think that I am tying myself down and making my life difficult. I guess I don't look at it like that, I think of it as doing something good, saving a life, doing my part, and I just wish that I could do more. I would love to start an animal rescue one day. That is one of my many life dreams. I just want people to understand why I can't say no...