Hopefully we can un-ruin that life of yours:
You mayhave to look in the mirror and ask yourself if you're being selfish/narcissistic.
You probably don't think so, which is understandable, many people with fetishes sometimes get that way, but stop and ask yourself: What am I doing for HER?
You have this fetish, (which will never go away, so get over that thought.) and you think "Okay, I can only get aroused by tickling....."
Okay, so....is your girl a robot? This view is what they mean when they say men view women as sex objects.
Sex is great, if both people are enjoying it. If it all becomes about what only one partner wants, that's a one way relationship destined for failure and hurt feelings.
What turns HER on? What does SHE like to do? Does she like her neck kissed, boobs kissed, back rubbed feet massaged, etc.?
Does she want YOU to dress any kind of way? Wear a certain cologne?
You can keep your tickling fetish (you have no choice) and can be extremely happy, but it'll take a lot of work, and "sacrifice." That's in paranthesis, because.....is playing with your wife's tits while she has a 12 inch smile on her face a "sacrifice?" If she starts playing with your dick, or giving you a footjob because that's what she likes to do to you....man, what a tough sacrifice!
The more you please her.....the more she'll be willing to be tickled by you.
Then there's all the other relationship things you need to work on and hopefully get right - being faithful, treating her right, being financially stable, helping with housework, respecting her friends and family, not being a loser who uses drugs or gambles, taking care of her when she's sick, listening to her, comforting her after she's had a bad day, encouraging her to pursue her dreams and better herself, etc.
It's all interconnected. The more that outside the bedroom stuff works out, the better the bedroom life will be!