Nice guys try to fix and take care of a girls problems and this is what her girlfriends are for. If its not a major issue let her be. Don't always go out of your way to please her, give yourself break. Let her solve some issues by herself, this will make her give you that respect which you deserve and that means you have other issues to take care of besides her.
2. COMPLAINING ABOUT BEING SINGLE
Stop telling your girlfriend how scared you are of losing her and been single if shows desperation and the fact that you show her you can't live without her is a really big problem. Girls always want to know that their boyfriends has other hobbies beside her. This will make her work to always get your attention because you are not always there.
3. BEING EMOTIONALLY DEPENDANT ON YOUR OTHER HALF
Women want a boyfriend, not a man that needs rescue. she will get bored of constantly feeling guilty for not being as nice as you should. A relationship should always be easy going, arguments helps strengthen and shows the level of love you both have for each other.
4. BEING TOO NICE
Girls absolutely love a guy who’s nice, but being too nice becomes a sin in a relationship because girls will always think there is an interior motive to you been too nice and its kills the vibe of the relationship. Girls will feel you just want to get under their skirts and there after dump them afterwards. So being too nice to your girlfriend makes her feel you have an interior motive towards your good gestures.