Small claims court hearing for unreturned sec deposit- Minnesota

[Albert George]

I have a past tenant of mine, who filled a claim for unreturned security deposit. Below is the situation

She broke the lease before the 1 year term. She violated the lease by having pets and when i enquired she was not willing to pay the pet deposit and terminated the lease early. I let he go and found a replacement tenant. I lost some money because i could only rent at a lower rate and few weeks after she moved out.

I sent her an email explanation before 21 days of her moving out on the loss of rent / advertising / marketing / showing expenses etc and mentioned i was at loss and cannot repay the deposit.

Questions : 

1) What are chances of defending myself at court, This is in Minnesota small claims court.

2) Is Email considered a valid medium of communication to send the Deposit statement explaining why i cannot refund deposit. I have a response from her on that to prove she received it.