You sound like two independent women who have each been living on your own for some time. Naturally, there will be adjustment issues around blending your households and combining pets in a household is certainly a common challenge. You are off to a great start by simply knowing that your dogs are compatible and play well together. And no doubt, in the time you have spent with one another you have successfully managed your differences in “parenting styles.”
As you may have already discovered, there are probably many commonalities in your approach to your animals as well as things that you differ on. That is one of the things that often separates people or brings them together in relationships. While I am not an animal psychologist, I do have a few ideas that may help smooth the transition for you, your partner and your pets.
There will obviously be issues of great importance to each of you and issues that you can be flexible on. In general, it is best that your overall treatment of the dogs be very similar. Feeding times, exercise patterns, and so forth are pretty easy to line up. Some issues are going to require compromise. If one of you loves to sleep with your dog in bed when you are home alone and your partner cannot tolerate this, the dog probably needs to get used to sleeping in his or her own bed, which can be in the bedroom if you both agree on this.
Other issues are important but may not be amenable to compromise. If one of your dogs has always been more of an inside the house dog and the other loves to be outside in cold winter weather, both you and your partner need to be willing to honor one another’s needs and preferences in this regard. If one dog requires special food or medicine and the other does not, you need to work out feeding arrangements that take this into account. It is largely common sense.
The main thing of importance is that when either you or your partner are home alone caring for both dogs, that they both be treated similarly with respect to house guidelines (one can’t be allowed to be under the table when you eat and the other not), but your dogs’ individuals differences also need to be honored and handled in accordance with each of your preferences. You don’t put an indoor animal outdoors all day in the cold just because it is more convenient for you. (A good quality dog door handles this nicely). Naturally, if one has a behavior problem that the other doesn’t have, that also needs to be handled differently.
With communication and an attitude of respect between you as partners around you pet ownership, this need not be a problematic adjustment as you merge your household. Best of luck in your transition.