Well I am an Adult Baby, I wear diapers out in public all the time (and use them).
People simply do not notice you are wearing a diaper, unless they are looking for one, and most people do not know what to look for anyway.
Most people will just think you have a big bum.
I have been out for the day wearing a diaper, onesie and dungarees, no one even bats an eye lid. The only time you have to be careful is if you mess your nappy, it takes approximately 7 minutes for other people to smell you, and a poopy diaper creates a more obvious bulge.
But still, as long as you change quickly after making a dookie people are not going to notice unless they are looking for a diaper under your cloths.
How many people do you know who go around looking at other peoples bottom and crotch, for that matter how many people do you know who wear diapers ?
Most people assume that you are not wearing a diaper, so they are not looking for it, would it surprise you to know that around 5.5 million people in the UK wear diapers because they want to ?
I would not worry, you are doing a very brave, kind, caring and loving thing for your boyfriend, if he likes diapers he has probably liked them since he was a kid. No amount of persuasion is going to get him to quit diapers, the best thing you can do is be supportive. Being negitive about it will make him feel depressed and that will trigger the binge / purge cycle.
The Binge / Purge
The Binge / Purge cycle is a cycle that infantilists go through. The binge is an indulgence in wearing diapers, adult sized baby cloths, acting like a baby, using adult sized baby furniture, playing with baby toys and even eating baby food. As you can imagine this stuff is not cheap, an adult sized baby crib cost 400 quid and adult diapers are about 20 quid a pack, and adult baby cloths are anywhere from 40 quid to 200 quid.
The purge is like the baby throwing his toys out the pram. An infantilist going through a Purge throws out all baby related items, and deletes all infantilism related media / browsing history from their computer, in order to try and distance themselves from babyish things and thoughts.
This rarely works, and usually results in a waste of money.
When the next Binge starts they go and buy all the stuff they threw out again, hence the waste of money.
Support your boyfriend, let him know you are ok with him wearing diapers. This is a Psychiatric / Emotional condition that is deeply rooted in the early years of his child hood, he can not help himself anymore then you can turn the rain off.
If it helps try to think of it as a neurological condition.
Be warned, do not be surprised if he asks you to treat him like a baby. This again is a deeply rooted need that all infantilists develop in early childhood.
He is still a man he will still act like a man and he is still capable of making grown up decisions, he is just in touch with his inner toddler.
"We do not want to be with children, we want to become the child"
A famous quote by a well known adult baby.
There is nothing sexual about being an adult baby, it may surprise you to know that infantilists are in many cases at more risk from pedophiles then ordinary children. The infantilism community is globally concerned with keeping children safe, both from pedophiles and from the influence of infantilism.
There is no known cure for infantilism and only one person has ever gotten over it, but that was by suicide.
I wish you and your boyfriend all the best, and good luck.