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Decay rates of the positronium molecule $\text{Ps}_{2}$ into two photons andinto an electron-positron pair are determined. Previous studies find that theserates are very different, \[ \Gamma\left(\text{Ps}_{2}\toe^{+}e^{-}\right)/\Gamma\left(\text{Ps}_{2}\to\gamma\gamma\right)\simeq250\text{(previous studies)}. \] This is puzzling since both processes have two bodyfinal states and are of the same order in the fine structure constant. Wepropose a simple calculational method and test it with the well-establisheddecay of the positronium ion into an electron and a photon. We then employ itto correct predictions for both these $\text{Ps}_{2}$ decays. We find thatprevious studies overestimated the $e^{+}e^{-}$ and underestimated the$\gamma\gamma$ channel by factors of about 5.44 and 3.93 respectively. Ourresults give $\Gamma\left(\text{Ps}_2\to  e^+e^-\right)/\Gamma\left(\text{Ps}_2 \to \gamma\gamma\right) \simeq 11.7$.

Rare decays of the positronium ion and molecule, $\text{Ps}^{-}\to e^{-}\gamma$ and $\text{Ps}_{2}\to e^{+}e^{-}\gamma,~\gamma\gamma,~e^{+}e^{-}$