Second best

I've Been dealing with a lot of lonliness lately, cause my best friend is in a relationship so she's been spending a lot of time with him, which I understand, but also most of my other friends have basically disappears because most of them proved to not be very true friends, and my boyfriend keeps bailing on me and keeps canceling, which I tell him I don't expect him to be constantly around, but like I've been feeling like I'm the second choice, or the convenient option when there isn't a better one, and like I just want to feel acknowledged and cared for every once in a while but I don't know how to let people know I have been feeling neglected and kinda used (if that makes sense) and such, and I also would like to make sure my feelings are justified and that I'm not being rediculous, because I have a hard time being sure about that