At this point in your life, you're too young to not be happy in your relationships. With the stress of overwhelming amounts of school work, a constantly decreasing bank account, and the pressure of figuring out what to do with the rest of your life, Your relationship should not be something that adds more burden to your already hectic life. The person you're with, whether it's just a hookup or something more, should be someone that makes you feel calm and happy. They should be your break from all the stress you deal with on a day to day basis. If they're just making you feel more overwhelmed, then they're not the right person for you.
You're in college, you're supposed to be having fun. You shouldn't have to focus all your energy into fixing something that seems to be broken more often than not. There will always be bad with the good, that's just part of life, but if you're staying with someone just for the sake of not being alone then you're doing it all wrong. I understand no relationship is perfect all the time, if it was that wouldn't be healthy either. But if you find that it's becoming more negative than positive, you shouldn't be ok with just having "good enough." You're too young to settle for average. You're too young to be putting other people's happiness so far above your own. You can't hurt yourself to protect someone else's feelings. You deserve to be happy just as much as anyone else.
Speaking from experience, I stayed in an emotionally abusive relationship for far too long. I didn't want to be the one that hurt someone else so I just let myself continue to get hurt. I was constantly made out to be the bad guy but continued to put all my efforts into fixing things that were well beyond repair. I put someone else's feelings above my own because I thought it was the right thing to do, but I didn't realize how much I was suffering until things ended and I became a much happier person.
If you're settling for anything less than amazing you're only holding yourself back from finding someone that will make you truly happy. There's someone out there that is going to treat you the way you deserve to be treated. So if you're settling for just "good enough" then you're not getting what you deserve. Find the person that makes you feel happy, that makes you forget about your stress, and helps you carry the weight on your shoulders without even having to ask. Someone that helps you with your problems, not add to them.