Most women who come out later in life does so because they fell in love with another woman. So, I want you to know that you are not alone. :)
There are two things I want you to be ready to accept before moving forward:
Coming out is a process unique to you and should be at your pace.
Your girlfriend has the right to choose to leave the relationship at any time if she does not want to be closeted with you.
I've been here and so I'm speaking from experience. This is a hard situation to be in for your girlfriend and undoubtedly you as well. The fact is you are both choosing to be in a closeted relationship. There are so many things you cannot experience because of hiding your truth.
It's okay to be scared but fear will rob you from the happiness waiting for you on the other side of it. The Bible says perfect love cast out ALL FEAR. So, how much do you love yourself--not her--but yourself. How much are you willing to sacrifice for other people's opinions and judgments.
There is a simple answer to your question but walking it out will not be easy. Fear usually arises because of the unknown. We don't know how to move forward. We need the exact steps. We need a plan. We need to see the twist and turns in the road ahead and try to plan for them.
If you're ready to gain clarity and build a plan to transition into a life where you can openly love the woman in your life give me a call.