5:24 PM PT — LiAngelo Ball just posted a picture with Rashida Nicole … seemingly making them Instagram official after Nikki Mudarris accused him of abandoning their family earlier in the day.

LiAngelo Ball is dealing with some baby mama drama … the mother of his 2 children claims he is walking out on their family after getting another woman pregnant and starting a new life with her.

The “Tweaker” rapper and basketball player has two kids with Nikki Mudarris … and the reality TV star claims LiAngelo just confessed to cheating on her.

Nikki says … “I see everyone has been sending me @gelo cheating on me. I want to clear this up and speak my truth. I am just as surprised as you are. We spent 3 1/2 years together, and last week he decided to walk out on his kids and tell me he got someone else pregnant (allegedly) and now is creating a new life with her.”

Nikki adds … “The ultimate betrayal is not even the word. My daughter is not even 2 months old, and dealing with this and postpartum is very hard. Please pray for me and my healing because I will get through this. I have to be strong for my kids, but I have absolutely no words.”

She also takes some shots at LiAngelo … “Karma is real and God don’t like ugly. I hope it was worth losing his family.” Nikki has since gone on her stories to claim he broke the news to her via text, blasting him as a “coward” and “pathetic.”

LiAngelo’s rap career is blowing up thanks to his “Tweaker” success … and he’s just been tapped to perform at the upcoming NBA All-Star Game.

Unclear who LiAngelo’s new alleged chick is, but Nikki says the woman is older than her. Nikki also has a message for LiAngelo’s new flame … “The same way you get them is the same way you lose them, thinking you winning by getting pregnant with a man who has a newborn is crazy work.”