attorney took retainer and has done nothing, and will not respond to calls or letter

At the beginning of the year I hired a family attorney to try and get full custody of my son in Texas. I have him a $3000 retainer and since then virtually nothing has been done. Never made it to court. Had two court dates reset. And haven't had any communication from my attorney except for monthly expense statements. My billing statement has at least five discrepancies for large amounts. Meetings that never took place etc. Last time I saw him in person I said I needed to clarify. After that I have called and sent a certified letter requesting copies of all files that I have been charged for filling, correspondence emails and other paper communications between both attorneys, and any other documents from the courts. No response. But he sent another bill. Literally the only communication from him is a bill. What can I do?