I agree with the advice here!
I also think it's important to build trust and intimacy without pressuring her for sex. Approach her for a back rub, put on some music and dance, or just wrap your arm around her while you're watching TV together. Start with these small things, and don't "hope" for sex afterwards. The goal should involve NO sex whatsoever with these actions. She needs to trust you first, and she can't relax and unwind if she's worried you're going to be pressuring her for sex. Gradually, over time, she will become more receptive to touching and physical intimacy.
Make yourself less available! Take up a new hobby--get out of the house more! Be independent, cheerful, and confident in yourself. She will pick up on these changes, and you will feel even better about yourself, regardless of whether or not the sex issue gets resolved. Forget doing chores as a way to get sex--as a female, I can tell you I'm NOT thinking about the laundry during sex. Asking if she needs "help" with chores is probably the worst thing you could do. Not only does it mean you have to do more chores, but it also means that she's going to be giving you orders as if she's a superior. Be proactive and take initiative when you see things need to get done, but don't make a big deal out of it...after all, no one gets a medal for taking out the trash, and you're a strong, capable man--you can do much tougher things than chores!
As far as buying her stuff...Maybe gifts aren't her love language (look into this book, the Five Languages of Love, if you haven't--it's pretty basic but has some interesting info about how people express love). Next time, don't buy things for her--but things for the two of you. Don't try to pressure her with a "romantic" weekend getaway--all she'll feel is pressure to have sex--but instead try something fun, like tickets to a theme park, an improv show that involves a lot of audience participation, an art gallery, or something else that's new and exciting. This will help her learn to let loose, and even if she hates it, at least you'll have some fun. If she's more conservative, she might interpret the clothes as a pressure for her to feel sexy when she's not ready. You can't change this by buying more stuff, but you can try other things.
I'm going to be honest here--if you make these efforts and don't notice any changes in her behavior, you might need to ask yourself if you can live the rest of your life that way. You haven't been married long, and it might be better to cut your losses and regain your independence. Only you can make that choice, but I highly recommend against staying in a marriage "for the kids." It will make you feel bitter, resentful, and anxious at best, and at worst it will turn you into a smug, self-righteous martyr who feels that his kids "owe" him for sticking around. What's more, your kids will pick up on it and have an extremely messed up view of what marriage is supposed to be like. Either you stay in it 100%--not just for the kids, but for YOU--or you leave as civilly as possible.
