Four sick calls in 15 months would be nothing at all. If you SAY you're sick, then YOU ARE SICK. The regs clearly state that it is the pilot's duty to determine his/her fitness to fly. It's really as easy as that. The law is on your side. DO NOT FLY SICK. The decision to call in sick when you are sick has nothing to do with how many prior sick calls you have. It is your duty, and the law, to not fly sick.

Now the above applies to when you really are sick.

As far as burning a "sick" call when you have no commuter clause and can't make the commute, well, the company's not really giving you any other options, are they. Do your very best to make the commute, within reason.

I will repeat: Do your very best to make the commute, within reason.

After that, do what you have to do, and don't look back.