Dejaye74,
It's good to hear you're making improvements in your life.
It sucks that you're sulking.
Figure out what you want. Wanting your wife (separated) to be happy is great. If that's all you want, then ask your wife if she wants a pet. That's harsh.
Do you have your own goals, your own interests, things you want to do, things that are important to you, things that your wife (separated) takes second place to? It sounds selfish, but it's not.
If you're worried about your own needs not being met in the relationship, it's not your wife's responsibility to make you feel wanted, or appreciated. Unless she wants a pet. Doesn't sound like it. That's stuff you gotta find in yourself.
You have to find appreciation for yourself, instead of being dependent on your wife (separated) to make you feel appreciated.
What are you doing that you're proud of, an accomplishment, something that you can make progress in, and see the progress? It could be be as large as a boat or rebuilding a vehicle. It could be learning a new language (including computer languages), starting a business, finding a hobby, seeing your son smile at you as he knows you have his back. Whatever it is, it's something you know you're doing and accomplishing, regardless of what anyone else has to say or do about it.
Not that it's all right to snap on people who get in the way, but it gives you something you are accomplishing. Think of it more as an exercise in self-worth.
What's the last thing you've done that you were satisfied to finish?
If you've made the last 13 years of your life trying to show your wife that you are responsible for her happiness, and that's your accomplishment, as if she isn't able to learn to be happy on her own, I can see that building some resentment. If you're upset that you've put in all that work and you're seeing her walk away without you getting anything in return for all your hard work, I can see feeling a profound loss that you're not getting what you feel you deserve.
Be happy for your wife, but don't be responsible for her happiness.
Be happy for yourself, find yourself, tell everyone who gets in the way of you being happy... tell them all off.
Find your own worth, by your standards that say you're worth it.
Let your wife live her life.
Live your own life.
Sure, you want your lives to be together, but that's two people who are living together, not two people who are trying to pretend to be one person.
So if you're lonely, knock it off. Quit being lonely. Make yourself busy. Find value and accomplishment in your own life for what you've done, not because your wife was proud of you.
And for your physical needs, there's porn, and lots of it, so you'll never get bored.