So difficult. I’d be the same. All you can do is be honest, but no doubt they’ll be a bit upset. X
Perhaps just have a kind chat about being excited about decorating the nursery yourself, and running out of space for their gifts? Maybe if they really feel like buying more things they could ask your opinion before doing so, or ask if there was something specific that you wanted to use to decorate with? Maybe you could give them pictures or links of what you’re looking for? Otherwise tell them that you’ve run out of space and still need to buy the essential stuff
I don’t think you’re being ungrateful at all. I appreciate it’s an exciting time for everyone in the family so people do get carried away but I do think you should say something as baby’s come with so much stuff anyway let alone stuff you don’t need or want! My hubby and I have been super strict with family and buying us stuff, we’re currently renovating a house and do not have room for anything that’s not an essential as we’re currently in a static caravan on site and have no space for anything that’s unnecessary! The wish list is a good way to move forward and encourage people to purchase from if they want to get you anything!
I wouldn’t say your being ungrateful, maybe just pull them aside and thank them and let them know that you haven’t really got anymore space for big things and that you’d like to get a few bits yourself. Maybe some of the bits can be used at a family members home, we had so much with our first that some was taken and used at my mums x