The worst family drama ever!!!

So this is like super long & mostly like a vent sorry I'm just so over my wedding now I'm hurt & at this point I just feel like eloping.
So just some fyi my "dad" & "mom" have never really been in my life at the age of 1 they left me at my grandmas house & never came back for a long time so i never really had a relationship with them
So 2 years ago I got engaged & I was so excited I asked my 3 brothers & 8 cousins to be in my wedding fast forward a couple months my "dad" has twin girls with his 25 year old wife (hes 40) so then the hot taken away for (surprise surprise) domestics violence & drugs & i didnt know until last year because I wasnt talking to him & I only found out because he got deathly sick from his oesophagus & almost died so his wife called me crying before his surgery so i put my differences aside & visited him & all that & now were talking again & hes feeling better. So after a fee weeks he tells me his daughters are eith his sister & shes on drugs & other things that basically convince me to try to get custody of them, but after a few weeks I start to catch on that they only want me to get custody because they want to come & pick up their daughters whenever they want so I stopped the process, THEN they get mad at me because they had ANOTHER child & that one got taken away because they still had an open case & I told them sorry but I cant Cate for a newborn right now (I'm planning a wedding & I'm only 20) so they stop taking to me & at this point I dont care anymore because he had never been there for me at ALL & only talks to me when he wants something. So fast forward to this past October my "mom" gets out of prison so my grandma (whom adopted me & is my bestfriend) & I take her into our home & she brings my 13 year old sister with her, well we had to throw them out 3 times & each time my grandma always let them back in, mind you my "mom" let's my sister do whatever she wants. She started having sex at 11 & now she wants to dress like a hooch & talk back to my grand which doesnt go fine with me so I ended up beating her up & they left for good & I told them I dont want anything to do with them anymore, so fast forward to last week my older brother A tells me hes not going to be in my wedding because all of a sudden he has 4 excuses but I know it's really because of my mom,(hes the closest to her) then yesterday my other brother AA told me if I dont invite my dad then hes not only pulling himself & my nephew (who is my ring bearer) out of the wedding but he will also not attend at all, & now I feel like crap because why should I please them when it's my day, am I wrong for not wanting my "parents" at my wedding because I am tired of the way they treat me, like I told my "dad", all my life I was chasing them so I can have a relationship with them but they never gave it to me but now I'm too old for this because I am getting married so they are no longer my problem or my main thought, idk I just feel like crap😔