Help My Elder Sister Is About To Marry A Man That Bad Mouths Her In Her Absence.

My Elder Sister has been engaged to this man for about 5 years now and then people have been complaining about their long term relationship. Even my mum at some point embrassrased the him when he comes looking for my sister, he promised her marriage but has not done anything about it since then.

when I asked my sister she said he is saving and planning towards their marriage but this same man has been living with his friend in a room since I knew him even though he has been working since I knew.

At some point becos of age (32) was no longer at my elder sisters side , my mum decided to give them one of her flats to leave in her 2 storey building house. my elder sister and my mum ultimately financed the wedding preparation even to the point of buying his own cloths for his own wedding and while her fiance's brother supported him with 250k for the wedding since he just lost his job last December.

Now what baffles me is that my sister appears to be the man while he is the woman in their relationship since I knew then, although I have always adviced my sister to be submissive to him and stop shouting and controlling her fiance. I noticed so many faults in him like not standing up to my sister to prove to her his the man in their relationship which is clear to everyone.

Now just three days to their traditional marriage I was discussing with him and he was bad mouthing my elder sister to me and he later told me "not to tell my elder sister ooo". I pretended to take what he was saying as a joke but deep in my heart, I feel my elder sister is about to marry a man she barely even knows.

pls whats your I opinion about this?