Mixed Signals, Red Flag???

My SO frequently makes comments about relationships that make me wonder if I should be worried. For instance, how he'd hate to have to share a bed with someone forever, and that if we ever moved in together he'd want to sleep in a different room some nights. And that he's surprised he doesn't hate me after our mini vacations because he normally can't stand to be consistently around someone for that long. Also that he never lasts in relationships for more than a year (we're at 7 months) and doesn't see the point in marriage. He doesn't say these things harshly, and he really treats me amazingly well, despite what he says. He's flown across the country to meet my family and made it clear he planned on seeing them again over the years and that he wants to be the last one I bring home.  He's also made it clear that he'll be crushed if I had to move away after graduation in December. However, I find my feelings are hurt sometimes because what he says obliterates any thoughts and hopes I have for us in the future.  And I'm constantly wondering if one day he'll just be over me. I love him with all my heart, but my head can't see reason in giving so much of myself to someone who may not be capable of long term relationships. Am I overthinking things or am I justified being concerned?