Hi there mama! I can relate to how heart wrenching this must be. Every mama and daddy want for their child to choose them over anyone else and I can assure you that your little one would too.
I would like to suggest, if I may, looking at it from a different perspective: since your child only gets to see grandma during those times, she/he might wish to spend time with her? I would take consolation in my children loving their grandparents just in case I may need them one day for a date night out with the husband or an emergency which requires a caregiver whom with my children are comfortable.
I honestly don’t think you’re being sidelined or not chosen over another - at the end of the day, she loves you and your husband very much and I can assure you that the bond it strong and she’ll still look to you for basic needs.
I hope my answer helps and I just want to say that you’re doing a great job. Parenting isn’t easy but we are all just trying our best to get through the good and bad days and that, to me, is a lot :)
Jamielene Fernandez