Can I be deported after a long marriage if I'm seeking divorce now and border patrol is called?

No, just because your card may have expired does not mean that your status has. Once you are a green card holder, you have that status for life unless you commit an offense that would make you deportable. You cannot be deported just because you seek a divorce. However, you should probably renew your green card or apply for US citizenship so you have a valid document as to your status.

More information is needed but if you have a permanent green card and you have nothing in your background that would make you subject to deportation you should be fine. With that said, you need to renew your card yesterday.