Do you want us to tell you what you want to hear or do you want the truth?
Having a girlfriend and committing to one woman isn't natural. When things stop being natural the vibe changes and the girl loses interest. I guarantee if you went out and ****ed a few hot chicks it would spice things up and probably save the relationship. Her respect for you would go up and she would start trying to validate herself. I am saying this to genuinely help you, if you love this woman and you want to keep her you will listen to me. I am not saying it will happen, but if some ****y player comes along and charms your girl you may be in trouble.
Take it from a guy that just had his girlfriend **** his brains out when she caught him out on a date with a bad ***** a few weeks ago. Yes read that correctly. Women don't leave men for cheating (if the girl is hot) but they do leave men who they lose respect for. And I have been in your shoes as well, had women with high interest level pursue me and chase me only to lose interest the moment I started committing. When you truly commit and stop gaming other women, you inevitably lose the abundance mindset. That is why you NEVER stop talking to other women. Dont gotta cheat, but if you see a hot chick in a coffee shop flirt! Chat her up!
Always remember this man, what women say they want and what they really want are not the same. They think they want a man that is loyal that treats them well, but they all want a bad boy that can replace them on a dimes notice. Women want to have fun. Keep things light, start chatting up some new girls. Even if you don't bang them, the mere act of going out and interacting with hot women will get your abundance mindset back and your gf will notice it. It is important for your girl to realize your a high value man with options, and if she wants to keep you she needs to not take you forgratned and meet your sexual needs.
****ing broads these days, American women are so entitled. If you were dating a foreign chick your situation may be different they tend to be more loyal.
Hope this helps brother