I am sorry you were in a relationship with someone who you once loved who lied and cheated on you. I am bisexual and have had almost every woman and man I dated or had a partnership with lie and cheat on me.
Cheaters and liars can all fuck off since I want nothing to do with them even as friends.
I was told by gay men who are friends that monogamy in same sex relationships is rare, and that most gay men lie but I did not know how true this was until I experienced it myself.
I am single, celibate, and alright with this for now.