Dear Amy:

My boyfriend and I have been dating for two years.

A few months ago, his ex-wife (they divorced three years ago) left her live-in boyfriend and hasn't been able to find a place where she can afford to live.

She lived with friends for a while, but their patience ran out. She basically begged my boyfriend to let her move back in with him and their child.

I told him this would be a problem for me, but I just found out that he did it anyway. His claim that it is for the daughter's sake is not enough for me.

He feels I am making this a bigger situation than it should be, and I feel that he should get her out of his house before I want to see him again.

Am I being unreasonable? In your opinion, is this in the child's best interest?

- Wondering Girlfriend

Dear Girlfriend: The current economic issues are causing some estranged couples to live under one roof because the family simply can't afford to sustain two households.

The child's best interest is served by having two fully functioning parents together in the home. Having one somewhat marginal parent use the home as an in-between crash pad? Not so much.

What's best for the girl depends on how skilled her parents are at explaining and coping with their choices and limitations, and how willing they are to put her needs before their own.

The biggest issue right now between you two is that your boyfriend was aware of how you felt about this and, instead of discussing it with you or even attempting to persuade you, he went ahead and agreed to this domestic situation without telling you.

That's the definition of a deal breaker.

Tell your boyfriend that you are also doing what you think is in the best interests of everyone concerned - including the child. Dad having a girlfriend around when her parents are cohabiting isn't a good idea.

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