Selena Gomez (right) and her friend Francia Raisa (left). Photo: Selena Gomez INSTA

Pop star Selena Gomez took to Instagram on Thursday to share a heart-warming story about her struggle and a friendship that carried her through.

Gomez recently got a kidney transplant due to Lupus, a chronic inflammatory disease that occurs when the body?s immune system starts attacking its own tissues and organs.

The 25-year-old pop star found herself at a loss of words to thank Francia Raisa ? her friend who donated her kidney to Gomez.

"There aren?t words to describe how I can possibly thank my beautiful friend Francia Raisa," she says in the post with a picture of herself and Raisa on hospital beds.

"She gave me the ultimate gift and sacrifice by donating her kidney to me. I am incredibly blessed. I love you so much sis," Gomez wrote.

The star says her disease "continues to be very misunderstood but progress is being made."

The pop sensation, who recently released her music album, has fought the disease with incredible resolve. We wish you good health Selena!