Parents in Law- different perspectives

Let your partner deal with it, it is their mother and will only cause problems if you say anything. Boundaries must be put in place before the baby comes.

Firstly congratulations on your new baby, 👶 exciting news for you and your partner. If this is your in laws first grandchild it will be new and exciting for them too.
It’s a shame you don’t feel comfortable around them and for them too because they will be aware of your feelings.

Generally grandparents do look forward to seeing their adult children and grandchildren, and some may feel they would like to see more of them especially if they are older and have health problems and don't get out much themselves.
There are many threads on the subject on here. These are your partners parents, and you both need to talk about and agree how to manage the situation, together,

Heavy

As a MIL it took me a short while to understand that my son and daughter-in-law had a life to establish as a couple and that my life and theirs ran along completely different dynamics.

Unless your MIL understands that your life, both as a couple and as individuals, does not revolve around her emotional needs, it is going to be a problem.

All you can do is stick to the boundaries you have put in place and gently explain that you have a busy life of your own to lead. You can assure her of your affection, and re-assure her that if you don't communicate as often as she'd like, it is not because you don't care, but because you are simply very busy preparing for the new baby ( congratulations!).

When an individual is emotionally dependent on another, it is a huge problem -regardless of the relationship between them. You will need a lot of patience. But stick with those boundaries otherwise you will be emotionally 'blackmailed' and the resentment will boil over.

Generally speaking, when our adult children get married and start a life of their own, we should already be leading our own lives; either still working or in retirement. I can only assume that your MIL is emotionally dependent on you because she maybe doesn't have a very fulfilling life of her own? Of course, you can't say too much on a public forum but, if that is the case, at least you will understand the reason for the intensity of her dependence on you.

All I can suggest is that you be very careful in your choice of words when communicating with her, establish a routine when the baby arrives, be as kind as you can under the circumstances. Other than that there's not much else you can do. But you are not responsible for her emotional needs.

you both need to talk about and agree how to manage the situation, together. Nothing to add this excellent advice from silverlining.

Firstly congratulations, an exciting time to come. I disagree with saying your partner should deal with it as you both need a united front else messages will get mixed. I’ve been a MIL for about a year and my granddaughter is nearly two. I also live in a granny annexe with them. I have my own life as do the main house occupiers and as much as I love seeing and being with my granddaughter they have to be left alone and I have told them to invite me to visit (next door) and I never impose myself on them. I look after her one day a week also. Your MIL and FIL have to understand and be invited into your lives. It’s not their right and the more they impose the more they will be excluded, because the more you will not want them there. Everyone needs to relax and enjoy the time to come. Good luck xxx

Where does your husband stand?

He is the one to make the situation clear with his side of the family

Heavy if you're feeling overwhelmed and panicky then however often you see your in-laws, it's too often.
Have a chat with your husband and see how he feels. Decide between you how often you are comfortable seeing them and start that now. You have your own life together and your mother-in-law needs to understand that.

For what it's worth I had to do the same when our first baby was born. We were expected to visit, 100 miles away, every other weekend. She would want to drag us round every friend and relative in town for hours to show our baby off: not good as I was breastfeeding.
In the end I said I would be happy if these people came to mother-in-law's house to see us, needless to say no-one was actually interested enough to do so 🙄
We soon stopped visiting so often as well, it was too much with a home of our own to run.

What a very kind thoughtful post Dickens ,wise words indeed.

Thank you for all the super advice

Great that the OP has returned to say thanks.
I think with hindsight, I kept too much in the background when my first grandchild was born. I was working full time, 100 miles away, and fully aware of the young couple’s need to establish themselves as a family, whereas daughter-in-law’s mum lived nearby. I think my son was hurt, with hindsight.
So my message is that communication is vital, both between the couple and across the generations.
I don’t think it is helpful to talk to parents about “boundaries”, though you may have that term in your mind. Nor is it helpful to hear that many grans are over-invested in their adult children and grandchildren’s lives, wanting to “ bond” with a tiny baby etc.