First off do the freedom programme.
2nd do a little research on online dating about red flags
Look up love bombing
Think about what your values are and what you want
Think about how you want to be treated and what your deal breakers are.
Write out a list of things you won't tolerate while online dating.
I don't think you need thicker skin at all. This is a learning process to decide what your values are and to learn about online dating.
There are a lot of fakes and weirdos online.
This guy could have been anyone.
Is this guy attractive?
Talking to someone online for 5 months is a complete waste of time.
This guy said all these nice things to get some sexy photos from you for wanking fodder. If he has attractive photos posted, he probably does it a lot. He knows exactly what to say to get results.
If you match with someone, do a couple of facetime calls right away to actually see if they are who they say they are. If you're still interested, arrange to meet them for a coffee within a week.
Take things very slow. It will weed out the losers.
Research him to make sure he is not married, has a girlfriend, or has a criminal record.
Sad it has to be this way but there are far too many liars online and you have to vet them.