I am not a physicist, but since light is a particle and a wave it would seem that light being matter would break down anti matter over time?
Like I said it's just what I would think and I could be insanely stupid and wrong lol
Nah, light isn't matter at all (a particle, yes, but not matter). More precisely: every particle has an equivalent antiparticle with exactly opposite charge (or other properties). For example, electrons are charged leptons with lepton number +1 and electric charge -1 (in units of electron-charge). The antielectron (positron) has lepton number -1, and electric charge +1. Conservation laws require that lepton number and charge be conserved, so the positron and electron can annihilate each other. The proton and the positron, however, cannot (as the proton is a baryon, not a lepton, and both have charge +1, so such an annihilation would violate 3 conservation laws). However, photons have no charge or lepton number, and thus conservation dictates that they cannot annihilate with electrons. Interestingly enough, they can annihilate with each other (photons are their own antiparticle).
This conservation is the entire reason matter-antimatter asymmetry is a problem in physics: every process we know of that produces electrons should also produce antielectrons. It's worth noting that the universe as a whole is not conservative (the expansion of space violates energy conservation, for example), so it isn't necessarily surprising to find an asymmetry, we'd just like to know by what process this comes about (of course, this is hard to do, as every process we can initiate does obey conservation laws: asymmetry may well only happen in some universe-level process, so we may not be able to study it directly).