To investigate the fatigue performance and reflection cracking resistance of super-flexible fluid mastic asphalt (FMA) mixtures, this study designed a super-flexible FMA-13 mixture by the mastic flow for filling (MaFF) method. The effects of temperature and maximum horizontal tensile displacement on the cracking resistance of both FMA-13 and GAC-13 (as the control) mixtures were explored via the Overlay Tester. Additionally, small-scale accelerated pavement loading tests were conducted to analyze the effect of load cycles on the rebound modulus of the FMA-13 mixture. A nonlinear fatigue damage model was employed to predict the fatigue life of both mixtures. The results indicate that when the temperature decreases from 25 °C to 0 °C, the load loss rate of the FMA-13 mixture increases from 63.2% to 72.5%, while that of the GAC-13 mixture significantly rises from 82.8% to 94%. Temperature has a significant effect on the reflection cracking resistance of the GAC-13 mixture, while the maximum horizontal tensile displacement does not significantly affect the reflection cracking resistance of the FMA-13 mixture. When the number of load cycles increases from 0 to 1 million, the rebound modulus of the GAC-13 mixture decreases by 32%, whereas the FMA-13 mixture experiences only a 24% decrease. Furthermore, the fatigue life of the FMA-13 mixture far exceeds that of the GAC-13 mixture. These experimental results demonstrate that FMA mixtures possess superior crack resistance and fatigue performance, enabling them to be used as functional pavement materials in stress-absorbing layers. They can address issues such as reflection cracking in pavements, offering broad application prospects.