Attending invitation

I always try to join every invitation. Because I know, when I invite anyone and then they don’t attend I feel very sad. That’s why don’t want to dishearten other. But sometimes people invite you but actually they do it to keep social relation, in their mind they don’t want to see you in their party. But how will you understand? Is it only social behavior or really wants you to see? In a party if I feel that people are neglecting me that is really some odd situation. I never join any party or occasion without invitation, and after getting invited, I don’t want to be ignored. If I feel ignored that makes me feel, I should have understand that they actually didn’t want to me see in their party.