Self-associating species exhibit highly nonideal vapor-liquid phase behavior in many mixtures, which is challenging to model. The most successful models, such as the statistical associating fluid theory (SAFT) equations, are based on Wertheim's first thermodynamic perturbation theory (TPT-1). However, despite its success, the traditional TPT-1 implementations of SAFT lack the requisite flexibility to account for the cooperative effects of hydrogen bonding observed in alcohol + hydrocarbon systems. The resummed thermodynamic perturbation theory (RTPT) provides an improved representation of these systems by considering hydrogen bond cooperativity. While more robust than its TPT-1 predecessor, RTPT has only been validated against computer simulations. In this work, we develop a form of the RTPT association contribution to the activity coefficient and fit RTPT parameters to experimental infrared spectroscopic data. The agreement between the RTPT model and the experimental data is striking despite requiring only one additional parameter compared to TPT-1. Calculated enthalpies indicate the occurrence of positive hydrogen bond cooperativity in all of the systems examined. Association constants fitted to the spectroscopic data are used to calculate activity coefficient contributions using a Flory combinatorial term. For completeness, regressions of vapor-liquid equilibrium data are included and utilize a non-random two-liquid (NRTL) model residual contribution.