This would then also apply to you...you caused pain in someone's life...

what did they choose?...

if they did not choose you, the person, what was your reaction?

Hello dunno

I was going to ask you what your usual approach would be .. laughing .. but I am not sure mingle is ready to hear it

A couple of obvious suggestions ....

Online refer to her user name .. (until she is happy to tell you her name) .

Avoid all the stereotypical comments .. hi beautiful .. hi sexy etc

Read her profile and show her that you have read it .

Put aside all the sexual energy you may feel when you look at her picture .. the goal initially is to connect intellectually .. it is okay to pay her a compliment but be genuine and try not to focus on the physical ... ..

Humour is always a good icebreaker...

Be respectful .. if she says she is not interested. Accept it and end the conversation politely .

Easy peasy .., best of luck grasshopper

Welp I'm not a girl (obviously haha) but I have a small amount of tips.
Of course online dating is different from in person. Typically you have more "competition" and less potential matches. Therefore when you discover a profile here that you think has the potential for a relationship, you have to make an impressive, otherwise she'll move on to the next one. That part I find hard because its extremely difficult to let your natural personality flow through an online website. This might sound weird but I'd consider that you make a female profile so that you can see the male profiles and see which ones are connecting and which ones aren't. If there are many profiles that seem and feel similar to yours (similar bio, same initial messages etc) than that might be your reason for struggling. Most importantly, I'd say for you to be yourself. People may not be initially romantically attracted to you, but they will respect your honestly, if you make the initial effort to show it. Be genuine and don't be afraid to throw yourself out there and fail.
I hope you do well, cheers my man