I have been married to a US citizen for 3 years, I have a green card issued almost a year ago for ten years.we separated and intend to get divorce.My husband was my sponsor and also I had co-sponsor.Co-sponsor wants to file for taking the sponsorship back and I don't know if that would mean that my green card would be taken away.Do I need to find another sponsor?How much time would I have if so?I plan to leave US in a while anyway,but I don't want to be in any way illegaly here.

You dont' necessarily have tohave a sponsor to keep your green card. I got divorced and had new one issued. I cant be of too much help but I certainly know that as long as you have been married to a US citizen for 2 or more years and had all your papers iin order you shouldnt have a problem ! I remember I had to show proof that teh married was based on LOVE ( ahd to show assets we had together , thigns in our name...)
I would suggest to either contact the nearest Immigration office or go there to get the right info.