If you plan on sticking with your spouse, then you're also stuck with your in-laws. Here's Dr. Phil's advice for dealing with your new extended family:
There can be no divided loyalties. When you get married and start your own family, that's where your primary loyalty needs to be.
Good fences make good neighbors. Your in-laws need to be your neighbors and there need to be really good fences up. Set boundaries about when they are and are not invited into your lives.
You've got a finite amount of physical and emotional energy. If your in-laws are draining you, you may need to change the boundaries. Reassure them that you are not closing them out, you are simply focusing on yourselves.
Once you've set boundaries, talk to your parents about them. They're not as fragile as you may think.
The other woman in every man's life is his mother. If your husband starts in with: "Well, my mother does it this way ..." then tell him to go over and sleep with her.
If a wife has a problem with her mother-in-law, it's the husband who needs to step in and help fix it. Likewise, if a husband doesn't see eye-to-eye with his in-laws, his wife needs to step in. The person with the primary relationship (the son or daughter, not the in-law) needs to be the messenger.
Negotiate with your own partner the role that you want your in-laws to have. Don't assume you're on the same page until you talk about it.
Try not to criticize your spouse for his/her relationship with his/her parents. It may only lead to more clinginess or complications.
You need to love your parents, and have a rich and active relationship with them, but any time that you turn away from your partner to resolve a relationship issue, that's a bad thing. If you have a problem in the marriage, you need to resolve it in the marriage.
Keep in mind that your parents only know what you tell them. If you go to them every time you're angry, and frustrated and having problems in your marriage, they hear that, but they don't hear when you make up.