I am not a monk and live the life of a layperson. Recently I have been entering and stablizing the 7th and entering the 8th shamatha jhanas. I am looking to get into dating with a mind to settle down in the future. I deal with social anxiety and poor self confidence with women. It was recently suggested to me to try visualization or affirmation right after jhana practice as my unconscious mind will be 'particularly receptive' to messaging.

Forgive me if this is not an appropriate topic for a thread or an appropriate use of meditation, but does anyone have experience with this or advice to help me in this vein? Would you tend to agree with my friend's advice or is that just bs?

Grateful for your time and energy regardless. Thanks.

Conflicting info. Your thread topic doesn't match the advice of AFTER jhana intentional changes. What are you visualizing/affirming?
Casting magick spells on yourself is fine, just think it out to make sure it is what you want, then go to town. Think it out like a genie's wishes. Then write down the actual well thought out goal/spell/intent/ what have you. 
​​​​​​​~D

I have no idea if this would work, but it's pretty standard to use the jhanas to improve insight, which is to say, use them for a purpose other than the jhanas themselves. Perhaps it might be a good idea to repeat the affirmation throughout the day, including after exiting jhana, so that you don't end up sitting down for the jhana with greed for an outcome, which could make it harder to get a good jhana. 

Jhanas could well be used for "worldly benefit" if they were not subject to the 3 characteristics. Chasing such an idea of "Jhana doing this or that for me" will likely cause more dukkha which of course is ok and can lead to the realization that "Dukkha does exist" no matter what I might have or not have. 

I would suggest observing the difference between Wordly vs Inwardly. Now THAT could lead to some juicy stuff!  

Might be worthwhile to look into the work of Daniel P. Brown on attachment. He has highly effective visualisation protocolls working specifically for self esteem and relationship problems. I think this is a good overview. https://open.spotify.com/episode/2R47P3CgfgQvxYbBB7yIxe?si=964a41fba6bf4f37

My advice is to become friends with your anxiety (it sucks and is difficult at first!), and just notice it. As you can sit better with the feeling of being uncomfortable, the aversion slowly drops, and when the aversion drops out then you can start to see the sensations for what they are. As you do that, you start to learn to see that anxiety was never the enemy you always thought it was.