PLEASE READ, THANK YOU SO MUCH
I've been having problems with my MIL for around a year now, it all started when I, for the first time in almost 7 years, turned around and said 'no' to her 
she lives almost 100miles away (I don't drive either) and kept going on and on and on and on about having my DD who is only 4 overnight for days on end. I politely kept putting her off but she kept going behind my back to my DH when I wasn't in and convincing him to basically make me change my mind. Caused a lot of grief between me & DH and finally I text her asking her politely to stop asking as it wasn't going to happen and to not go behind my back etc.
Many things have happened since, interfering, ridiculous amounts of FaceTime calls per week to DD on DH's phone, name calling to me over the phone (two faced cow, bad mother, bad wife, controlling, silly child....) because I've said 'no' and started being more assertive. It all hit a head again over Easter because she was asking what to get DD for Easter. I said an egg, just like everybody else, after all, when did Easter become about iPads and the like?! She got huffy and waned to spoil her (as usual and which we don't agree with as we want to bring DD up to be grateful and count her blessings).
I'm sure she does this to look 'better' than us as we can't afford named brands etc (not that I'd spend crazy money like that anyway). She always goes ridiculous for Christmas/Birthdays etc... making us look bad and her like 'the one that will get DD anything she ever wants' (sure this is deliberate 
) anyway, I said no, just get an egg like all the other children in her school will be getting, a few days later we get a package full of clothes after me repeatedly saying just an egg will be fine. I contacted her about it and she said 'she will buy DD whatever she wants and won't be dictated to by me, a silly child' (I'm 21, studying for a degree with a PT job, training and a small buisness for goodness sake!) I said well I'm her mother and I'm afraid what I say goes but she wasn't having any of it 
it's almost like she thinks DD is hers IYSWIM?
When she calls she's not bothered about speaking to DH, just says 'where's my baby'?! I'm sick and tired of it and don't know what to do. DH has only just started backing me up, before he was to afraid to upset her it seemed, she's quite manipulative with him but I was getting really hurt in the process she also says things to DD on the phone so she'll pester me for things or to go somewhere. Like at Christmas I overheard whispering in a separate room asking DD whether 'she'd like to stay longer and if so, she'll have to ask mummy'. Clearly done secretly and not expecting to be heard.
She's due here on Wednesday and I really don't want her to come if I'm to be honest, I know she'll play mind games and do the things I ask her not to do (like take DD to the shop and not just buy her one or two things but the whole frickin' shop or want to go somewhere extravagant which again makes us look bad as we don't drive so can't really get to many extravagant places but we do do other things like country park outings, wood walks, parks, swimming etc...)
This is just a snippet of what's been going on 
WWYD ladies?
I feel so anxious and depressed and am so worried for the future with her I can honestly see he turning DD against me with her manipulation or extravagant expensive gifts I've put up with this for 7 years now and only just started to stand up for myself but all that seems to be doing is causing problems and guilt