She likely is deeply insecure. At the root of all clinginess is deeply engrained insecurity. She may be afraid to be alone. She may have trouble standing on her own two feet, being independent, and being her own person apart from a boyfriend and the child. She may need to display her "happiness", her child and her relationship all over social media because she needs approval from others in order to feel good about herself and her life. That is not uncommon. Ironically, it's usually the unhappiest people who need to flaunt their "happiness" on social media. That's my two cents!