CMV: A friendship between a single and partnered person is inherently unequal/ unfair

I would actually love for someone to change my mind about this because i'm struggling with a lot of resentment for my friends recently. I (26F) am one of the only two single people in my friend group of around 7 women. I've been reflecting a lot and realizing how lonely i am, even though we all live in the same city and two of my friends are actually my roommates. I find that my roommates are constantly spending time with their boyfriends and on top of that, always invite their boyfriends to everything. Yesterday, for example, we went to the bday party of one of our friends and both roommates invited their boyfriends. I spent the whole pre and journey to the party as a fifth wheel, which is a common occurrence for me that is becoming unbearable. i mean, it sucks to just stand there while the two couples are in each others arms lol.
Anyway, I've realized on a deeper level that all of my friendships feel unequal. They are my go-to support system, but i am not theirs. They are the first people I want to tell things to, but I am not that for them. There are so many life celebrations centered around coupled people: engagement, marriage, pregnancy, etc. They get to have these extravagant parties and be celebrated. Not to mention the additional celebration they get from their partner (for example, on valentines day). Speaking of which, i absolutely hate "galentines" day with coupled friends because it really just feels like a pity party.

It all breaks my heart because my life is centered around my interpersonal relationships and it just sucks that my friends are more important to me than I am to them. And it makes me hate them. Even worse, i absolutely dream of being in a relationship, but haven't met someone with whom i've connected to like that. All i have is a bunch of failed dating stories that serve as entertainment for my coupled friends.

How are us single people expected to be friends with coupled people? It's so incredibly lonely and unfulfilling.