Something has to give here

I'm going to have to be a real fucking bitch or else I am going to let The Ex drag me right back down the same path all over again...He is getting totally irate with me because Truck Driver keeps calling me while I am at work...I keep my cell phone in my pocket and I keep it on vibrate so it doesn't ring while I'm doing something, but if I'm not busy with customers when he calls, I take his calls. And if The Ex happens to be around, then that is too bad. I tried to work things out, he wasn't having it, he moved on. Now it's my turn. But he still keeps calling and chatting with me on-line and he keeps dragging me back down...And, of course, I let him do it to me every time. Aside from changing my phone number and my screen names, I don't know what else to do...Any suggestions??