One of my shia friends do not abstain himself from eating haram foods saying that he do not follow such rules(he do not follow Anyone Akhbari)yet he attend majlis & does azadarihow to deal with such friends as he makes everything najis as he do not make himself paak after taking haram foods(foods from hindus).
friendship is good but a religious friend is better than other
so abstain is your job not his job