You are a 12 year old kid, probably transiting from child to adolescent stage. You might be going through some biological changes physically and also the level of maturity will grow gradually. You have mentioned that you can have happy moments with your friends. You haven't mentioned about how and what you feel when with your parents and other family-members. It is best suggested to work on building rapport with your family members ALSO and not limit only with friends. Talk to your parents about how you feel.