Why is it so hard finding friends when you're a mum

I'm two kids in now and I've come to realise I'm rather thin along the ground for having real friendships. Since the age of about 30 I've realised that I am lacking a space in my life for a best friend, a close knit community of friends. And then along came having a baby and all of a sudden I found a new hurdle in the way of making friendships and keeping them. Right now, I'm lucky to have a very very small group of mum friends who I get on with but with having more than one child and another on the way our schedules are changing and with that opens up, for me, the need to make some more friends whether they be mums or not.

I'm 34 now and a fairly social being - I like to have plans, I like to chat, I like to go out with or without kids but mostly I crave interaction. But making friends in this day and age is HARD. All too many times I find people flaky - its a pet hate of mine. If you want to meet up with me - meet up with me, if you dont or have no intention then dont make plans with me, and then there's some mum friends who only like to do things with their kids which is absolutely fine, but I'd love to have friends that can do both - surely having the opportunity to sit in peace whilst eating a croissant and drinking a hot drink whilst conversing with likeminded women isn't a bad thing!?
Some only like to go out and do activities at attractions whereas i like doing everything on a budget so even a cuppa round mine is welcome.
But mostly I find it hard to make friends because there are too many mums out there living a competitive life when it comes to raising kids. I am what I am - what you see is what you get. I swear (alot) and I feed my kids jam sandwiches and let them eat haribo as a treat - thats me. I totally get I'm not everyone's cup of tea, but in this day and age shouldn't we be accepting of others and their ways of life? I dont harm anyone and I adore my kids sometimes a little too much. My parenting isn't perfect but then who's is? is there a right way to parent? I welcome all mums and all kids - I dont think any child is naughty, nor do I think any mum is too earth mother - we are all on our OWN journey through motherhood where there is no written right or wrong (obv apart from harming children but you get me)
Just the other week I toddled off to a toddler group with both girls. I decided now was the time to put myself out there, make friends, make the effort. However upon arrival I was ignored, stared at, told I shouldn't be drinking coffee (because Im pregnant) and then stared at by the many tight knit groups of women/mums thats surrounded the circle play area. I felt out of my depth, scared and in the spot light. I tried to make chat with one lady who then proceeded to keep telling me I have my hands full, how Paige will have the "poor middle child syndrome" etc all advice that someone you haven't met, probably didn't need.
To me motherhood and pregnancy included, isn't a race - there is no child that progresses too early or too late - they simply do it at their own speed when its right for them. There is no perfect or easy pregnancy or birth - all pregnancies and births are incredible in their own ways. Everything about this stage in a woman's life is equal to the next. Why, do we, in conversation feel the need to compare and contrast - of course listen to one anothers stories and experiences and delight, rejoice and entertain them, but for heavens sake dont compare them to your own, they are individual. Is this why I struggle to find friends for life? Am I picking the wrong type of women to try and be friends with?
For me, my friendships come above and beyond most things and I will go 110% for them. If I make plans with you I will damn sure make sure I am there. If I say I'll do something or arrange something, I will sort the shit out of it good n proper. There is never too much effort on my part - I go all in. I'm so stupidly loyal that personally I think I need to be reincarnated as a  war dog or something because I will never ever leave my band of friends, I will do anything and everything for them, sometimes to my own detriment of my own health. but why do I find others not like this? I'm easily forgotten, I get let down alot, people dont socialise with me or want to half the time. People never ask me about me, never show an interest in me and will often talk over me or glaze over in conversations.
Back at an old job I took a Dale Carnegie course which I swear changed my life - it taught me so much on how to conduct myself, how to have friends, how to be a better person. Dale Carnegie was the person that wrote the book "how to win friends and influence people" and let me tell you, this book was everything to me to read. It made me conduct myself so differently. The one thing I remember vividly was to how to create an interest from people and that was to always talk about THEM - everyone loves talking about themselves, it makes them feel cared for and wanted and so here I am, at 34 STILL living my life this way and yet I am lonley.