Massive stars are key ingredients to galaxy evolution, through their powerful flux, winds and final explosions. The resulting compact objects are extreme systems, capable of accelerating matter up to relativistic speeds, leading to very high energy emission. Eventually, their mergers can result in the gravitational waves, and mutlimessenger signatures. In this talk I will present snapshots of the lifecycle of massive binaries based on high resolution numerical simulations. The latter reveal the structure and dynamics of the winds and jets. I post-processes them with radiative transfer methods to produce model data that I directly compare with multiwavelength observations. I then show what gravitational wave detections can tell us about massive binary formation and evolution through cosmic history. My talk will highlight the capabilities of hydrodynamic simulations combined with refined emission models in the context of future multi-wavelength and multi-messenger observatories.