Honesty, communication is the most important thing people can have in a relationship. Without it relationships can’t help but become dysfunctional and eventually, if nothing is done by both people, they inevitably crash and burn.
If they upset you, tell them, but not in a way that shames them for what they’re doing. For example: instead of saying “you never help me clean the house” say “could you maybe start cleaning the house with me? That’d be a massive help”. Basically treat your partner like a fragile child who needs constructive criticism, not scolding.
When they’ve done something you really liked, tell them. it’s just as important to let them know when they’ve done something good, as well as something bad. Tell them that you really appreciated what they did, or you liked it, give them a kiss, show them affection, you’ll find that they’re a lot less hostile towards you once you show you appreciate what they do.
Fucking commit to them, for Christ’s sake. Modern relationships largely lack commitment, and I don’t just mean saying ‘I love you’ through Snapchat every morning and putting their name in your bio (sly dig at my ENTIRE generation there, don’t take it personally). I mean really fucking commit. If you and this person really click and genuinely love eachother then commit to them. Think as if you are going to marry them one day and believe that thought. The things you think and speak become your reality, so you can do your best at training yourself to think a certain way, therefore changing your reality.
Here’s the bottom line: not all relationships are salvageable. You have to spot problems early and solve them soon enough to carry on being with said person in a loving and appropriate manner. If the relationship is completely dysfunctional and has been for a long time, unless both of you bust your fucking ass to get it back on track, chances are it’s not possible to resolve.
Catch problems early and don’t let them become the focal point of your relationship.