"in love"? please help interpret

LeAnn

Could you be with someone who couldnt tell you that theyre in love with you? I asked my fiance (at the time he was my boyfriend) and he said "I'm just not really sure what being in love is anymore. i thought i knew before with girls in my past but obviously i didnt. i can tell you that i love you more than I've loved anyone else and that when im with you i feel happy but when youre not with me I'm sad. I love spending time with you and can picture a future with you. But I'm just not really sure what 'in love' is exactly". Can anyone clarify what this meant?? I'm comfused. i dont know whether to feel flattered or upset.