You have to have your own personal goals. You need to maintain the friendships, hobbies and interests that you had before you met your partner. If you give these up for the sake of your relationship, you are giving up your life. When your partner first met you, they were attracted to you as an individual. Maintaining your individuality will enable you and your partner to build a mature loving relationship.
Many relationships fail today because one partner has given up too much of themselves for the other.
You have to love yourself first, before you can love another. If you enter a relationship and give up all the things that define you as an individual, you are not giving yourself the love that you need. Sooner or later, if you lose your identity, if you stop giving to yourself, you will be unable to give to your relationship. It's important not to confuse identity and individuality with flexibility in your relationship. Individuality is about the things that make you who you are.