A relationship between an openly queer person and a closeted one is more difficult than a relationship between two closeted persons. Dating a closeted person comes with many restrictions and conditions, but the love remains the same between any two people regardless of the coming out status in society. A person who hides his/her sexual orientation and plays hard not to reveal it to get rid of unfortunate circumstances is a closeted queer person. It's hard for a closeted person to deal with themselves and it is also hard to deal with their relationships too. These are the ones who can easily get targeted for their open-mindedness in the community. Yes, some hypocritical mindsets in the LGBT community point out the closeted people. Instead of understanding them and their situation, most of the people judge and criticize them. Of course, due to their hidden status, they won't get targeted by the society, but they get screwed up by people in the community who are aware of their sexual orientations. It's difficult.
Love can't be controlled. It can happen to any person and at any place. An open queer person may fall in love with a closeted one and that is inescapable, but dealing the situations between them to take it further from dating to a committed relationship, includes many things to be followed. Nothing is impossible if a person tries his level best to achieve it.
If you are an open gay/lesbian/bisexual/transgender/genderqueer, whatever, and in love with a person who is extremely closeted but deserves all your love, then you must take few ways to lead your love life in the right direction to reach a fruitful relationship.
Patience is the most important thing to deal with your closeted partner. Unlike you, he may take time to explore himself and get ready to see the things the way you see them. Do not rush and freak him out. Give him enough space to get comfortable and enough time to open up himself and yes, this happens even though you know each other very well.
Always remember, not to impose your opinions on her because this may suffocate her and make her end up faking her personality for the sake of your love. Your way of thinking can be opposite to her way of thinking when she is outside in public. So, try to understand from her point of view too.
When in public, your closeted partner sees the world differently. So, don't expect any lovely gestures like public display of affection and do not force your partner if he/she is not comfortable. Respect their opinions. This doesn't mean you should stay away from them. Make them comfortable enough that they approach you to hold your hands in public. Love is not about forcing, it's about making other people feel loved.
Your closeted partners become so comfortable in between four walls and shower all their feelings for you in various forms and gestures, but when it comes to their public behavior, they become a different person. Sometimes, you may feel like you are talking to a stranger. The strange vibes fill the void between you in public. It surely irks any open queer person, but when you tag along with a closeted one with you, you must deal with it.
The relationship between you and your closeted partner can be known to your circle of kin and kith and do not expect that your closeted partner can reveal about his/her relationship with you to his/her kin and kith. It takes a lot of time to make it happen.
Always try to make your closeted partners comfortable in opening up themselves instead of poking the same matter, again and again, to make them feel uncomfortable about their hidden orientation. Understand they already carry heavy baggage inside of them for not being able to lead a life they want to. Your harsh words may be stressful for them. Take a deep breathe and be patient enough to accept the way they are.
Handling of emotions could be difficult for both of you in public. Like you, your closeted partners also feel the same, even they may want to hug you or kiss you more than you want to, but they may feel their hands got cuffed up because of the society. Understand these little things and act upon them by caressing them and make them feel happy.
Always try to encourage them for being what they are, rather than complaining about their efforts. Your efforts as an openly queer person may be easier for you, but it may be difficult for your closeted partner. Without adjusting yourself in a relationship for a while, you can't take it further. Adjusting, controlling and convincing yourself are the tasks you must be pro at while dating a person who is closeted enough and of course, it must be for a while and not forever.
You must be cautious enough about the surroundings and the people around you. Being an open person, you might be good enough in taking criticism, but for a closeted person, even a little comment may affect much on him/her. In public, you must take some measures to get rid of unfortunate incidents.