Do not let your emotions do the talking.
Most people know better than to make major career decisions when they are emotionally charged or upset. The same rules should apply to an emotional relationship. Major relationship decisions should never be made in haste or in the midst of an argument. If you cannot have a calm and collected conversation about your relationship without getting upset, it is best to reserve that conversation for another time when you are both in a calm place. When you do this, you are less likely to say something that you do not mean out of anger.
Do not let the small stuff ruin a good thing.
This seems like a no-brainer but there are many people out there who get annoyed by those pesky little relationship annoyances and let them balloon into something bigger and irreparable. If everything else about your relationship is on track, you trust each other, you're attracted to one another, you respect each other etc... look at compromising on some of the little things that bother you.
Ask yourself how you feel about yourself in the relationship.
If you like yourself when you're on your own, but find yourself always feeling insecure or turning mean when you are with him, you should reconsider your relationship. Are you able to be yourself with him? Do you feel confident when your with him? Is it as though you are a better version of yourself when you are together? If your answers to the last three questions are yes, then your relationship is likely a healthy one and serving you well.
Do not ignore the big things.
There are bigger issues in a relationship that should not be ignored just because you are in that happy place together such as cleanliness, family values, drugs and alcohol and financial matters. Is he is a slob? Do you both want the same things in terms of family and future? Does he do drugs or drink more than you would like? Are you similar when it comes to money matters with regards to spending it and saving it? Are these things that you can deal with or are you in it hoping that it will change later? Chances of change are always present, but you should keep in mind that the person you have before you today may never change. If you are not comfortable with the person you are with today, you should perhaps rethink whether you want to be with that person long term.
Do what you feel is best.
Deciding whether or not to stay in a relationship is indeed a stressful situation. Keep in mind that your relationship should serve both you and your partner and ideally you should both be better versions of yourself when you are together. If you find yourself asking the question of whether to stay or go, you need to think about what you really want and how you truly feel before making your decision.