It would not be considered an eviction. You are technically on a month to month lease. Even though you do not have a lease you are technically a tenant and it is recognized as a month to month lease. Your room mate can decide not to renew the month to month lease and give you 30 days to vacate. It is a non renewal of lease. The room mate is technically your landlord since she is on the lease and you are living there.

It is not considered an eviction.

If you get the 30 day notice in writing and do not leave during that time. Then eviction proceedings would start. It would be an eviction with cause at that point. (You didn't leave when you were given proper notice, etc...)