To be fed up with work colleague!

[Crimble123]

Im finding it almost insufferable working with her. We have the same role but she thinks she's my boss when she isnt.
Im not the loudest person but will hold my own in meetings etc. I don't feel like I need to talk over others and make it about myself.
However work colleague is so loud! Often talks over others including me, makes it about herself. The other day a new person came in to meet us. Colleague made it all about her and she would do this and that and come to her for this and that. Not "we" meaning me and her.
So I did cut in and said oh btw im Crimble I do the same job as colleague and this is my other colleague1 who does a different role.
Other senior staff are asking colleague to hold meetings that I also should be apart of as I have information to add that is valuable but because is loud and all about contacting her for this and that people go straight to her.
Ive already approached our boss once to discuss issues but this basically got batted away. I got the sense from boss and other colleague they are worried about rocking the boat as other colleague1 has mentioned about walking on eggshells and worried about saying something as they know other colleague will get in a mood!
I just don't know what to do. I feel undermined most of the time, Im made to feel like a junior member when im not and my boss has once already batted off me asking to speak to her about these issues.
Im feeling so angry and frustrated

You're not alone OP. I manage someone who undermines me, or tries to. Something im going to have to address as she does it in meetings when she has her 'audience' pain in the arse and quite frankly a b*tch

So I think you need to raise the meetings thing with your manager. That’s not acceptable and your manager needs to
make sure you are included.

Also from now on do not share anything that could be remotely helpful with this idiotic colleague.

You get a lot of dimwits who think forceful people add more value. Also those who think women need to act like men to get ahead at work. Women who do this are often the absolute worst kind of managers and are vile towards other female colleagues.

@Crimble123 pretty sure that your job does not include showing her how to do the bits of the job which need to be done on excel or any other computer programme/ she is obviously not as capable as she likes to make out. you should not help her do the job which she is supposedly able to do. tell her directly that you are doing the same job as her as she is not your superior, so you wont be taking insults or orders from her! tell hr the same!! they need to train her and not expect you to train her!

By doing that though that's going to create a hostile work environment isnt it?
She's really friendly with the boss and seems to have a way with manipulating people. A woman she's been vile to at times was in our office yesterday acting like her best pal saying she would help her and share a spreadsheet with her.
I just think everyone tiptoes around this woman!

Before complaining you’d be best to have plenty of concrete evidence of her problematic words and actions and to have evidence you’d tried to address it directly with the colleague. And to be clear on what you’d like the boss and colleague to do.

Most of the examples you describe would be difficult to evidence.

I once had a more subtle colleague, senior to me, who’d undermine me, cut me out of information of relevance to my work, meetings, work tasks. She was quieter about it. I decided that it would be difficult to evidence and that she’d likely be even worse if I raised things with her. I left!

Today I raised it with my boss. I didnt directly say it was colleague but said I felt we weren't working as a team and I felt I was being left out and made to feel junior. Thankfully this time she listened and raised with colleague that we need to work together. Colleague then laughed and said its just so easy to lone work isnt it. So boss has now seen im not the issue. I also spoke up with another person who said they would send something to colleague. I said please could you also copy me into anything you send colleague. I hope im making it clear now that I am to be included.

In the 50s, a quickie had about the value of an A level, nowadays it's probably worth a Masters !