Stop obsessing over a past relationship
Stop nagging
Seriously, stop. Take a step back and figure out the big things about your partner that truly bother you, and approach him/her from a place of concern and support, instead of nitpicking for sport. That'll get you nowhere.
Get over needing to be right
Learning to say "I was wrong" is a skill worth learning.
Take care of yourself
No relationship can be successful if you don't feel good about yourself, both inside and out.
Know what you need and then ask for it
You're dating a human, not a magical psychic.
Take a class
Couples who learn together connect on a deeper level. Find some common ground (cooking? art? science?) and go from there.
Stop complicating things that aren't complicated enough
If you bemoan the fact that your relationship is going too well, you might need to revisit why you're constantly seeking out drama.
Assume that if something was said that hurt your feelings, it wasn't intended that way
Why would they want to upset you or hurt you? Give your partner the benefit of the doubt, but if it's really bothering you, don't be afraid to bring it up.
Write notes
Whether you have study hall together or live together, handwritten notes are personal touches in today's highly digital world.
Pitch in
Help each other with chores and other necessary, if banal, activities-cooking, cleaning, re-organising, etc. Not doing them if you live together can create tension, and always doing them can create unfair expectations. Act as a team of equals.
Disconnect
Step away from the laptop during quality time. Everything on the Internet will still be there later.