The stuff I was hoping you weren't lacking, you're not. That is good.
Let's try to pick apart the problems (if any) with your communication. Fight me on this stuff if I am wrong even in the slightest way because I don't know jack shit about you. Maybe all 6 girls were approached by the hottest guy in the world walking out the door after your date, seriously idk.
Do you feel as though you're coming across as too needy?
Do you feel as though any neediness may be causing girls to see you're trying to get way too serious, way too soon?
Do you think the dates are particularly fun (for both parties), or that you're communicating a message and an image instead of focusing on having fun?
Albeit you know just as well as I do that tinder and other social networking sites that link people up for dating are taken very lightly. These are the backbone of online fucking. They work, but only to a certain extent. So regardless, you cannot give weight to what is occurring with this.
Nevertheless, from what I've read so far, there is nothing wrong with what you're doing. Just like I thought in the beginning. You're displaying what a girl would think of as a nice guy who is probably pretty serious about life and looking for a girl to be with, etc. This is fine. But when it starts to repeat itself, that means somethings gotta give. They're not going to. So maybe its time to rearrange how you go about this. This doesn't mean fall off the deep end and get to dinner, ask for it to go, and say, "you can eat it off my dong."
Instead what I mean is to contact much less. When you're actually talking on tinder, tell them about yourself and ask about them. Play the nice guy card you are right now. That works to get you a number. It should. Then as soon as communication begins over text, slow down. Text less frequently. Stop making jokes about marriage. Let them come to you. Desperation can be smelled a mile away by a woman. They're like sharks. You don't need them. The second you start to feel as though you're falling off the wagon again, train a third or forth day a week or go to another meeting.
Keep yourself occupied with "YOU" things. Don't keep yourself occupied with "them" things. Pay less attention to them. It will probably be hard at first but its a habit and you already know how to break those. Think of this as a game of tug o war. You give her just enough rope... as soon as she think shes going to win, pull back and start over. This is until they're hooked. You know they will be because they will be kissing you at the end of the date and/or texting you the next day. You won't need to text them.
So basically, ease up. Make your primary concern fun. You don't want to be seen as their Dad, but more as their fun new man friend they're trying to fuck. Let the serious stuff come out sure, but reserve a short window for it. and maybe most of the stuff that you're speaking about now is second or third date stuff and not to be brought up on the first date. FUN, FUN, FUN, FUN. I DO NOT CARE, I DO NOT CARE, I DO NOT CARE, I DO NOT CAR.
You will now see after getting their number and the initial green light to meet up that texting 60-40 or even 70-30 is much more suitable. Don't drop off, be smooth about it and wean her. She won't even notice she is doing all the contacting if you're at it right.