You ABSOLUTELY CANNOT be evicted for "having" bedbugs. The landlord is required BY LAW to exterminate all vermin in its apartment buildings. See Civil Code sections 1941 and 1941.1 (rental unit must be substantially free of vermin [bugs] or it is untenantable). You cannot be evicted for asking the landlord to exterminate bedbugs. You have no responsibility to pay for extermination, even if your lease illegally says that you do.
You can fight this eviction and win. You should also talk to an attorney about suing your landlord for the bedbug infestation and retaliation. Bedbugs can carry serious diseases. Landlords that ignore this problem actually make the problem worse by spreading the bedbugs throughout the building.
I am doubtful you can be evicted for bed bugs unless having bed bugs is a violation of your lease. You might want to read your lease and see if there's anything in there that possibly pertains to this issue. Also, what does the eviction notice say? Is this a 3-Day To Perform Or Quit notice? Do you proof that this is a complex-wide problem as opposed to just your unit? I think landlord would have to prove that you caused it.