3. You’ve become someone else
Good relationships allow people to be themselves. It’s natural and expected to put on a bit of an act toward the beginning of a relationship, within reason. You might make an extra effort to laugh at their jokes or pretend you are more interested in their hobbies than you really are. In most cases you can chalk that up to wanting to make a good impression at the start of the relationship. We all do that to one degree or another.
Once a relationship is well established, acting in ways that do not reflect your true self to impress someone should not feel necessary. Sure we all do or say things to avoid making our partner feel bad whether we have been together for a week or for 50 years, but that’s decidedly different compared to when we tend to go a bit overboard to make ourselves look good at the start of a relationship. You should not feel like you have to keep putting on an act and presenting yourself in a different way in order to convince the other person you are worthy of their love and admiration.