TBH I don't struggle with DDD at all as wolf. This is a match up that laser spam will make the match. You can easily outrange him with laster, they key here is that u want him to be the attacker. Also if you downsmash when he grabs wolf will duck under his grab and hit him, hard to do but effective if ur friend has a grab pattern. Other than stick to quick combos when inside and save smashs for when u are behind him. Also don't get into roll fests with him, feel free to roll away and start laser spam again. He is slow in the air so should dominate him there as well.
As Wolf, Dedede isn't tough if you know how to DI out of chain grabs. Your best defense against him is to not let him grab you in the first place. To do this, I always keep my distance at first. Just mainly use your blaster and don't attack him at close-range unless your sure he won't be able to grab you. Once you hit around 50%, his chaingrabs become very easy to escape, making his most dangerous tactic useless. With that out of the way, DDD isn't tough on the ground, his smash attacks are slow and easy for Wolf to punish. Also, it's a lot easier to pull off Wolf's spike on DDD than it is many other characters. But if you want to try that, make sure to practice it first.
I don't struggle too much with Dedede. However, I am going to have to disagree with your laser spam method. Usually Waddle Dee spam will out do laser spam.
Also, could you clarify what you mean by, "DI out of his grabs," because you can't DI out of a chain grab, or at least his. Directional Influence is just that, influencing your direction. However, this pertains to you only when you are airborne. Dedede's grab does not send you into the air, so it is impossible to DI "out of." Your best bet is to go with something quick, like a shine, to get out. However, if he does the chain grab correctly, even a shine won't get you out, but it is still your best bet. Space yourself with Bairs.
Learn the lag times that Dedede has with his attacks. Do that and only his weak attacks will get you. Basically, you dodge an incoming attack and then retaliate.
What... kind of advice... is that...?
As for your, "people say I'm better with Olimar," compliant, I know. I used to be the same Way. The best I can describe it is Olimar is easy to learn, but hard to master (or easy to abuse, hard to master), where as Wolf is rather slow on the learning curve. It takes a lot more experience with him than Olimar to use him efficiently. When I imported the game my Olimar was a million times better than my Wolf, yet I forced myself to use Wolf and get better with him. Since then I developed Wolf Walling and my Wolf is now much better than my Olimar, I think, but my Olimar still remains a force to be reckoned with.
Don't "force" yourself to main Wolf just because you want to (even though that's what I did, lol). Just do what comes naturally to you. If you find yourself saying, "Man, I like this moveset," go with that character. I wanted to main all the Star Fox characters, but find Fox unbearable to play as, sadly, so I dropped him.
In time, grasshopper.
