Lease Breaker with vague threats

[Stephen E.]

I currently have a married couple as tenants who are breaking a lease eight months early. I have made them aware that they are liable for rent until the unit is re-rented or the lease term expires, whichever is sooner. My tenants are recently discharged bankrupts who with some family help have put together money as a down payment on a property. They are concerned about the prospect of having to make both rent and mortgage payments at the same time. Today I received a very irate email from him advising that I had been the cause of many sleepless nights, that his wife had fallen down stairs at work he claimed as a direct result of this, and adding rather darkly that,

"You've entered an area you are not prepared for. Get this dump rented out and leave us alone."

(The property is an appealing townhouse, recently painted, new carpet, private garden and attached garage.) I should add that he appears to be an alcoholic, I have been over there at 10 am and found him drinking from a super sized can of beer (to calm nerves perhaps, this was the meeting he announced they were breaking the lease).

I find this tenant to be aggressive and believe his manner is intended to interfere with exercising my rights as a landlord. Having said that in my jurisdiction while he is liable for rent as outlined I have to make reasonable efforts to mitigate the loss by trying to re-rent the unit.I need relations to be as constructive as possible to keep up with showings and re-renting the unit. In line with this I am due to be over there at the end of the week for two showings. Our agreement has been that they vacate the property for showings although he did not do so for the last two. I do not look forward to going over there and I do not relish dealing with this tenant. Crazily his behavior harms his own interests: if he interferes with my ability to re-rent then he is on the hook for rent himself.

There are a number of options. One is simply to ignore this; he could have been drunk when he wrote it. He has been up and down before. Another is to write and state clearly that they are in breach of contract and are the authors of their own misfortune, and that if there are any more threatening communications we will be forced to take action. If he keeps up with vaguely threatening language I guess I could have a lawyer review it or simply present it to the police. I need to keep showing the unit, and they are not planning on moving out until June. I don't want them out before then, I just want new and qualified tenants to take their place in time for this change over and constructive relations in the meantime.

There may be other options besides ignoring this or writing to restate the position and warn him off from further threatening language. I basically want to be in a position where I can do what I need to as a landlord in these circumstances, free of this kind of trouble. I would welcome hearing people's thoughts on options.