Perisistent coughs like you describe can be from several things. I can only echo what wonko said. My first thought was also gastro-esophageal reflux. You don't have to have a history of heartburn to have significant reflux. When reflux goes up far enough it stimulates secretion of mucous in the lungs. This causes a cough.
Reflux is occasionally related to MS if the stomach is not emptying properly. But it is more related to gaining weight, family history, and eating habits.
Another possibility is very mild asthma which can cause a persistent cough without really being short of breath. Reflux can also make asthma worse.
Consider post-nasal drip if you have a constant feeling like there is something in your throat that you can't quite swallow. Allergies or sinus trouble, smoking or living with a smoker, can cause this.
Then there are more serious things that present first with a nagging cough.
Bottomline, this is worrisome in itself, but is impacting your social life. It should be reported to your doctor and taken seriously.
Good luck and let us know what turns up.
Quix
Sorry to hear about your cough.
I have a few thoughts:
Are your coughs productive? That is, does anything come up when you cough? If so, take a look at it. If it is not clear, that is a sign that you could have an infection. Even if it is clear, I think if you are coughing up "gunk," it may indicate an infection. Do you have a fever or anything else that you associate with the cough?
How long have you had the cough? I see it's been long enough to disturb your social interactions.
Another thought is that perhaps it's not your lungs, but your stomach. You can have "silent reflux," where you don't feel the burning but stomach acid is still coming up and irritating your throat. This can lead to coughing. I get an annoying tickle and cough from reflux.
I really hope you can talk to a doctor about this, I'm just a community memeber trying to offer some advice, but if it is as bothersome as you indicate, it may be worth a doctor's visit.
Good luck and take care!