I don't think anyone can answer that question for you. My idea of living comfortably may be completely different from yours.For example, a friend who is visiting said that some of his friends decided that Panama was an extremely cheap place to live. Why? Because of the cost of beer! The important aspect of their comfort and cost of living was based on the price of a case of beer!
You can check out some rental and real estate prices on Buscando Casa which I have included a link for. By searching the local newspapers you may find some better prices.
The rental deposits here might make a big initial dent in your budget... as most landlords will ask for a 5 month deposit (the max allow by law)... a few will ask for more. With luck you might get away with less. If you rent through a real estate agency you'll pay a 1 month commission for a 12 month lease (1/2 month for a 6 month lease and 10% for shorter lease). That means you could be looking at shelling out 7 months rent to move in.
The Buscando Casa website won't help you select which neighborhoods or cities outside of Montevideo you would be comfortable living in. Nothing beats a trip here where you can walk through the neighborhoods and spend time in them.
Will your lifestyle involve eating out 3 times a day? If so, I think you'll find it quite expensive here (compared to Central America and Asia anyway). For the quality and quantity of food eating out may not be that expensive.
However, unlike Costa Rica and the Philippines, you are not going to find lunch for US$2 in a restaurant here.
In the Winter here, what level of heat are you planning on for your house/apartment? Nothing but a gas space heater to keep your toes warm now and then... or a warm comfy apartment 24 hrs a day?
My recommendation would be for you to plan a trip for several months, if possible including some winter time here... to explore the different areas and how your lifestyle fits in here budget wise.
Some differences you might find... restaurants serve just oil and vinegar for salad dressings. The grocery stores carry a few of the U.S. brand name salad dresses... with a price that might shock you! Which do you need to be comfortable?
If you want to live in the country you'll need to consider transportation options. In Montevideo, I see no reason anyone would consider owning a car. In the country it might be a necessity and could easily blow your budget.
I think people do live comfortably in Uruguay for the budget you mention. I don't know if YOU can.
I live on a small farm about 5kms from the local town. Excluding foreign holidays, the two of us live well on 40000 pesos a month (currently 1, 666 U$S) which includes running a car and small motorcycle, health subscriptions, paying local taxes, visiting MVD or Bs As for imported luxuries every so often and eating out twice a week.
From what I hear, life in the big city is rather more expensive... possibly because there are more things to spend your money on. :)
Patrick.