Military Relationship

So My Boyfriend & I Have Been Dating For 3 Months & He Just Joined The Army So He Is Gone For Basic & Came Back For Xmas & New Years & He Left On 01/02 And Im Sad All Over Again .. My Mom Tells Me All The Time That I Need To Really Figure Out What I Want To Do If I Cant handle Him Leaving For Months On End .. Is It Normal To Feel Sad Everytime He Leaves ? Or Am I Just A Baby & Dont Want To Be Alone ? I Am Fine With Not Being With Him All The Time But Now 5 Months He Will Be Gone & I Cant Help But Feel Like Unless I Marry Him & Leave My Life Behind & Moved With Him Im Going To Be Alone Most Of My Relationship.. Is This Normal Or Am I Just Being Over Emotional?