Is this relationship worth waiting on?

I met this man over the internet and we have been in a relationship for over three years. We don't see each other often because he is a workaholic and I have health issues that don't allow me to travel. (I've checked him out, googled him, am sure he is not scamming me, etc., just to get those issues out of the way.) My major problem is that I feel that I am the lowest priority in his life. He owns a small business and employs several family members so his job and his family are intertwined.He works literally about 16 hours a day. It just frustrates me terribly that two or three days may pass without hearing from him. He gets sick and doesn't tell me about it, doesn't return phone calls or texts.,etc. We have talked about me moving to his area and possibly getting married, but I worry that I will end up more lonely out there because I will be leaving my support system of friends and family behind. How do I assess whether this relationship is worth holding onto?