Will you ever accept an open relationship out of love?

so my crush does not want to get into a relationship with me because he is still seeing his college lover (they know each other since 5 years and has been LD since 2 years). we got into an argument because of this and he blocked me.
when i dug deeper, i found the girl dating another guy. she posted a pic. there is no pic of her with my crush but on my crush's profile he post picture of him and that girl.
when my crush saw that pic, i think he got jealous and unblocked me.
Coming from south Asian background, i know my crush and i we don't have such culture to accept open relationship (otherwise dating a girl here would not have been an issue).
He did not tell me but i think he did his first time with her. He always travel to go see her.
Does their relationship sounds healthy?
Will you ever accept an open relationship out of love?
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