Female nature: Hypergamy (google it). You are not alone, most men are in your position, only one Chad away from getting dumped or cheated on. Its nature, dont hate the player, hate the game, good looks are associated with good genes so she wants to seek out the most attractive male to reproduce with and if she comes across another male that she deems to have better genes aka a better face she will jump ship and onto his cock. It is what it is.
50% of wives admit to cheating
56% of wives admit to feeling they had to settle for their husbands
1 in 3 married men are unknowingly raising children that are not biologically theirs.
50% of marriages will end in divorce with 85% of divorces being initiated by women.
The list goes on.