Am I just crazy or is it normal for me to feel very sad when my boyfriend leaves

I've been with him for a year and and 7 months and I love him very much. He's like the one I wanna spend the rest of my life with he's perfect even though he can piss me off. But anyways we don't live together yet but it's like every time I have to leave or he leaves I get so depressed an it's like when I wanna see him again he would be like damn babe I just saw you yesterday maybe another day an I respect that if he has things to do I'm not that type of girlfriend who wants to be so controlling and crazy that's not me. But I need to learn to live without him without being so damn sad all the time sometimes I think to myself girl what the hell is wrong with you you act like your never gonna see him again and it's like this everytime smh I keep myself busy but I just wanna know like am I crazy or is this just a normal feeling