What measures do celebrities take to protect their images from being used for commercial purposes without permission? How much does this typically cost them?

From a legal perspective, they rely on the various state and federal laws that give them actionable claims against people/businesses that use their images without permission. A few examples of these laws are:

Send off a Cease & Desist demand ($XXX to $X,XXX)

Take the lawsuit through trial ($XX,XXX to $X,XXX,XXX+)

What should I do if I love a girl and she apparently doesn't love me?

Common Law - Varies by state. Many states recognize what are known as “the four privacy torts,” which include “appropriation of another's name or likeness.”

As far as the cost goes, that will vary depending on how far the celebrity has to go. Aside from the deterrent effect created by the mere existence of the laws (cost = $0), a celebrity may need to hire a lawyer to:

The Lanham Act - Federal. While the Lanham Act is generally thought of in the context of Trademark law, Section 43 has a provision regarding “false endorsement” that has been used by celebrities (notably, Carmen Electra) to fight the unauthorized commercial use of their likeness.

I caught my husband of 20 years looking at inappropriate pics of women on TikTok or Instagram. I'm not sure., but when I told him he got mad and made excuses of why they popped up. I then told him how I've snuck on his phone and saw what he's been looking at . We had a horrible big fight. I asked him why did he even marry me when I see the type he likes . Nothing like me, I'm petite, blonde and blue eyes. These women are dark haired dark eyed and have curvy bodies, large breasts, etc. I just don't feel the same about him after this. I can't get over this

Right of Publicity Laws - Varies by state. Some states have statutes that specifically forbid using a celebrity’s likeness (and even voice) for commercial use without appropriate permission.

File a lawsuit and push for early settlement ($X,XXX to $XX,XXX+)