I have read many, many experiences of those on this forum who were teenagers in the 60's and are very bitter about making a decision to get baptized as a child.
Ummmm... wait, dear MG (again, peace to you!): they made a decision. Probably one no one could talk them out of. Based on what they knew/understood/believed at the time. So, they regret it now. How many made the same decision and DON'T regret it? Should NO young person be ALLOWED to get baptized because SOME regret it? What of those who got baptized at, say, 30... and now regret it?
People make all kinds of choices... throughout their lives. Some they regret, some they don't. Some who marry young eventually regret it; some don't. Some who marry OLD... eventually regret it; some don't. So what? Some people get their license when they're young... and end up dying in accidents. Surely, they parents regret letting them get a license, let alone drive. Surely, that child, if he/she had it to do all over again... would wait to get their license/drive? Right? Sure... But if your argument is correct, we should prohibit ALL young people from getting their licenses/driving.
Some women have children young... and eventually regret it; some don't (I absolutely didn't and don't, and yeah, I had mine very young - and they have been the JOY of my life for more than 30 years!). Some wait and have them older... and eventually regret it (because they're just too tired to deal by that time). Should women just stop having children... young AND olders... because SOME regret it?
How is the decision to get baptized as a teenager any different from making a decision to get married as a teenager...
For some, it is quite different. Some find it easier to walk away from a marriage than from God. Most JWs, however, find it easier to walk away from God... than from a marriage. Because, based on the WTBTS teachings, they're not marrying God; heck, they're not even in the New Covenant - Christ is not THEIR mediator, so... they're not really walking away from God... are they?
Again, your position on this specific matter (the OP's marriage)... at THIS point in time... is utterly ridiculous. No, I don't expect you to see that... but, trust me: it is.
Again, peace to you... and I do mean that. Peace... such that you move your mind past this matter... that really is and should be of no concern to YOU... because the "little girl"... is all grown up, a mother/grandmother/great grandmother... and nothing your rant speaks to can/will change that. So, really, what is the POINT? There is none... so... let... it... go... and regain YOUR peace of mind!
YOUR servant and a slave of Christ,
SA