Elaina Bellis' body struggled to produce enough breast milk to feed her twin girls

Credit: James Branaman

It’s one of the often-unspoken pains of post-partum – the struggle to breastfeed.

In a relatable post that quickly went viral, Elaina Bellis, mom to newborn twin daughters, wrote about being unable to produce breast milk after desperately trying.

“It was devastating,” Bellis, 29, tells PEOPLE. “You have these humans inside your body that your body is building for months, and all you want to do is to be able to provide them with what they need, and build up immunity – especially because my girls were born five weeks early.”

“Breast milk is the best milk you can give them to help them grow, and the fact that I couldn’t do that just tore me up inside. I struggled with that emotionally the entire first month of them being here and they’re only five weeks old.”

Bellis went through a “traumatic” birth, involving two blood transfusions and an emergency caesarian, plus a build-up of excess fluid in her body, which slowed down any production of breast milk.

“My pituitary glands and the tissue in my breasts wasn’t able to form the supply because of all the fluid,” Bellis says. “I’ve been told by many different lactation consultants that because of the way my birth went I’m not able to give [my daughters] as much as I’d as hoped.”

Her struggle to breastfeed is even tougher to take because Bellis knows she can produce plenty of breast milk – she did a year and a half ago, after she gave birth to a stillborn son.

“After we lost our son, every time my shirt came off my milk would shoot across the room – I kept leaking for months and months,” she says. “I had a full supply but no baby.”

“I knew it wasn’t a problem for me. So when I had the girls and I wasn’t able to do it, it was really frustrating for me because I knew I could in the past.”

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Bellis and her partner, James Branaman, are thankful for their friends, who stepped in to provide their girls with breast milk, which they supplement with formula.

“One friend was coming to visit, and was like, ‘Can I bring you paper towels, toilet paper, can we bring you coffee, or breast milk, ha?’ She was joking and I was like, ‘Breast milk, please bring breast milk!’ ” Bellis laughs.

Another friend, who had a baby six days before the twins arrived, has an oversupply problem, and comes over every five days with enough to feed Bellis’ girls at least two bottles a day. Bellis says there’s no chance she’ll suddenly be able to produce more than the 1 oz. she gets out each day, and “surrendered” to her breast pump.

“They’ll still latch on to me because they are getting some of my milk, but mostly we have this formula and breast milk from my friends, so they’re getting both. They get about 8 oz. of breast milk and about 10 oz. of formula [each day].”

After sharing her story on Instagram, Bellis was amazed by the response from women in support, with many of them facing the same problem.

“It was overwhelming, and just my heart feels for these women and their stories. I wasn’t expecting any of this – I’d just been thinking about how hard I had struggled with it,” she says. “I just felt really called to share how hard it had been with my breastfeeding experience because sometimes on Instagram there are so many women who portray this beautiful life of motherhood, and breast milk is flowing – and that’s beautiful and that’s their truth, but I didn’t want to portray that I was all rainbows and sunshine when really I was crying and having a hard time.”

“I just felt like – ‘I’m going to share what’s really happening with me,’ and when I did, I felt like women really related with that and felt comfortable being vulnerable. It’s blowing my mind!”