I suspect that most LDRs are difficult; it's hard to get a connection with the person who perhaps once was in contact with you every day.
Email is something to try, if your partners check and answer their emails. Or if they don't, even snail mail. It's important for you to let them know that you need more contact.
You might also see what other social resources are available in your area. Try googling "polyamory" with the name of your state or town (e.g. Arizona polyamory), and find out if there are any poly groups close to you. Or, just look for clubs of anything you are interested in, so you have a chance to be in contact with some nearby people.
It is hard to have people not get what polyamory means, so Polyamory.com is a valuable online community you can turn to.
You are in a tough spot; I am sympathetic.
Love means never having to say, "Put down that meat cleaver!"