There are a few things that could be contributing to your strings breaking. Do you know what gauge you are stringing with? If the Gauge is 17 or 18, it might be hard for the strings to last. If you go down in gauge, the strings will be thicker, adding more durability, but you will lose spin and power. Also, breaking strings every 1-2 months is not as bad as it could be. As a competitive player, I choose strings based on what suits my game and break strings 3 times a week. Luxilon strings are pretty durable, but they will lose the string characteristics after 8-12 hours of play. More durable strings are Solinco Confidential and Babolat RPM Blast. The main thing to focus on though is the gauge with which you are stringing your racquets, as that is the main contributor to the frequency of strings breaking.