  Motivated by a recent experiment directly measuring the current-phase
relation (CPR) in graphene under the influence of a superconducting proximity
effect, we here study the temperature dependence of the CPR in ballistic
graphene SNS Josephson junctions within the the self-consistent tight-binding
Bogoliubov-de Gennes (BdG) formalism. By comparing these results with the
standard Dirac-BdG method, where rigid boundary conditions are assumed at the
SN interfaces, we show on a crucial importance of both proximity effect and
depairing by current for the CPR. The proximity effect grows with temperature
and reduces the skewness of the CPR towards the harmonic result. In short
junctions ($L<\xi$) current depairing is also important and gives rise to a
critical phase $\phi_c<\pi/2$ over a wide range of temperatures and doping
levels.
