“struggled mightily.” The Hebrew word is actually to crush or oppress, and it suggests a mighty struggle. Rebekah knew what was going on inside her was not normal so she sought Yahweh about it.
“If it is so, why am I this way.” The meaning of the Hebrew phrase in this context is uncertain. The literal is basically, “If so, why I this,” which is idiomatic and fleshes out to more like “If this is so, why am I this way? But what Rebekah meant by that idiomatic phrase in this context is debated. One suggestion is, “If it’s going to be like this, why go on living” (CJB). But that meaning is extremely doubtful. Another suggestion is, “If it is going to be like this, I’m not so sure I want to be pregnant” (NET). That translation seems to be a modern sentiment erroneously moved back into the biblical era. Pregnancy and having a child in that culture was so important to a woman (and these were her first children) that it is unlikely that she would have not wanted to be pregnant. To us, a much more likely meaning in the context is “Why is this happening to me” (HCSB; NIV; cp. ESV). It makes sense that Rebekah, after asking herself why this was happening to her, went and sought Yahweh for an answer. In seeking an answer from Yahweh, Rebekah is a good example to us. Too many people wonder what is going on in their life but never diligently ask the Lord for an answer.