I love a co-worker and don't know what to do.

[RomanticMan]

well you dont work together now so why not tell him your gay , and ask if he is too  - the worst response will be no response at all and he stops messaging you , if your ok with that risk then just tell him  - every other reply will be better , even if its just to say hes not gay but happy top be friends , but theirs always that chance he feels the same

We still have mutual work friends and he's also in contact with them too. So, if he tells other people about it, it may risk and ruin my life and especially career.