should I do nothing?

Do nothing for now. Keep communication open with your neice, so that you can be there if needed at a later date.

I have faced this in the past with my daughter, once it was a dreadful controlling boyfriend and the police were involved at the finish of it. The second time when she married someone who just wasn’t right. It ended in divorce. I didn’t interfere in either case simply because I was terrified of losing her. I married a man who had been divorced and his first marriage had taken place behind his family’s back because his father had told him he shoukdn’t Marry her and the family didn’t like her. MOnica is absolutely right, these marriages do take place, sadly. My DD was divorced. What we all did was to make very sure she knew we all loved her and never, ever said “we told you so” when it was all over. It was so hard to watch. She’s married again to an old boyfriend and they’re so well suited and happy but she can’t have children. But that’s another story’s,

Having worked in domestic abuse I would say please keep doors open. Your niece may need someone to be there for her one day.
It doesn't sound like a good start though does it...
A close family member was involved with a controlling man and he did everything he could to cut family out.
So if you currently have any contact with your niece keep it going if you can. If you don't usually contact her, you can always pick it up at the wedding by saying "how lovely to make proper contact again". Send jolly texts ( but not only texts as phone may be controlled), postcards from holiday to them both maybe, anything that says subconsciously that you are with her.
Perhaps this will all be unnecessary (I hope so) but at least you will know that you haven't just ignored your concerns.

Keep out of it.

I cannot help but think that your post is a perfect illustration of the different ways families operate. Ours is a very close family and we would express and possibly discuss concerns relating to other family members. I would not see your involvement as intrusive from the perspective of a family that probably operates in a similar way. I would see it as counter productive in this instance and would recommend that you keep your council and just take a supportive role if things all fall apart. Good luck and best wishes to you ?

It’s harsh, but MYOB. Interfering will do nothing but harm to your relationship with your niece.

I agree with others, this is a mine field and one many have to face with loved ones. Head versus heart. She is an adult and entitled to make her own decisions, mistakes etc But so many times when things go wrong I’ve heard or read “ I wish I’d spoken up”. I would stay close to her, phone calls, meet ups etc not as a way of spying, just so that she knows you are always there if she needs you. If he tries to isolate her from her family, then that would be a cause of concern to speak up. But then as others say, do they listen anyway .... yes a proper mine field, good luck ....

Do absolutely NOTHING, not even talk about it to anybody. Too many maybes. Maybe she is being considerate of his feelings about the job situation. Maybe he is insecure and this comes across as being critical . We none of us know the ins and outs of other people's relationships and you wont be thanked for trying to solve anything or say anything as this can be seen as interfering and meddling.

Definitely don't say anything. It won't make any difference, you won't be thanked for speaking out. As the old saying goes 'love is blind'.

It is hard to hear of things going on in the lives of people you care about, and so tempting to speak up. However, like most posters here I do feel that this will not end well if you do. The couple themselves will probably be angry, upset and might well contact you and it likely won't be pleasant; your own DS and DiL will then be embroiled in a situation that won't make them very happy, and all in all I do feel that 'a still tongue in a wise head' would be the advice to follow.

Say nothing! This is a mine field! niece will not listen as she already knows her BF short comings and intends to go ahead. The only thing likely to happen in my opinion would be a family argument!

No I don’t agree at all Clare please don’t invite your niece and partner over so you can spy on them what if you do that and take a dislike to him what are you go8ng to do then ?
It is not your business nor is it her parents business she is an adult in her 30 s with obviously a well paid job
I find it very uncomfortable that you are all discussing and discecting your nieces love life behind her back
Let the girl sort her own life out she has a close family to fall back on if ever needed Blimey I d have run for the hills if I d had a family poking into all my mistakes you ve got to kiss a lot of frogs to find the prince, let her be and stop all gossiping about her behind her back

Keep out of it let her sort her life out you wouldn't be thanked.

Maybe it would be a good idea to visit/invite over your niece and her fiancée regularly .
That way you can get to know and make up your own mind, about this chap. And make it clear to your niece and partner that she has a loving, supportive family in the wings.
If that's not possible, then regular telephone chats with your niece to keep communication channels open and be there for her.
I don't believe age is an issue when you're worried about someone who may be vulnerable, or in a bad situation. Context is everything.

Thank you MissAdventure, a timely reminder. I think I am safe from identification and I hope that catlover is.

I think you should keep out of it.

At most, you could casually ask your sister-in-law how she gets on with on with daughter's fiance.

Tread carefully.

I think that as you have found it necessary to ask you should probably keep your own counsel and not discuss this with anyone, including your dil. Things can get distorted and get back to the people concerned.

In my niece's very close family it might be OK as they all do so much together as one big united family but I think that is very rare.

Just a reminder that threads here can be put onto Facebook and Twitter.

Catlover, you have my sympathies. Families operate differently. In my family, we have been in a similar position, and like yours, there is concern and involvement with nieces & nephews. We discuss our worries in this way, we consider it our business, and don't see it as gossip when it is just us - uncle, aunt & cousins.

Having said that, I would agree that you should be very careful about saying anything to your niece's parents. You might be able to say "What do you think of him?" in a very general way, which would invite them to share concerns, but would allow them to "toe the party line" as well. If they don't share concerns, then I agree that there is nothing to be done.

My own children have tried to keep an independent relationship with their cousin, so she can chat with them away from her husband (who worries us a great deal). I have been as neutral as I can with the parents, helped by the fact that a baby was conceived very early in the relationship - so I ask lots about how the little one is developing and give lots of praise, so managing to avoid talking about the father at all!

I wish you luck, and hope that it turns out better than you expect. In the meantime, this is a forum for support

thanks, it is difficult because I am very fond of my niece, SalsaQueen, she is an adult as you say but I feel she is quite vunerable, and hate to think of her marrying a critical and controlling man.
We are a pretty close family, but I can see from the replies that you are right and I shall just have to step back from this.

Verging on gossip!

Agree, stay out of it.

I agree with MOnica & Iam64 it's not for you to get involved.

This is a woman who is in her 30s, not some teenager. She isn't your daughter. Why do you concern yourself?

Keep out of this. If anyone wants to get involved, it needs to be your son or daughter in law, who had first hand involvement, certainly not you.