Braces?

So I had braces for 18 months about 3&1/2 years ago. I wear my retainer at night but within hours of taking out the retainer, my teeth are spaced like I didnt even wear it. Is this something that is my orthodontist's fault? How can I fix it? I have an appointment with my orthodontist in a little over a month. I'm considering braces again to fix the issue but, I do NOT want to pay, but i don't really know of another way to fix my teeth.