Yes, it's correct. Here's a simple rule: With the exception of 'to', you should always put the verb into the gerund form when it follows a preposition (with, of, from, by, at and so on). 'For' is not possible, because 'for' can't connect these two verbs. 'For' would have to be followed by a noun e.g. 'struggle for money'. 'To' can, of course, connect two verbs, but in this case the verb would have to be in the infinitive i.e. '...they struggle to readjust'. 'With' is the only possible preposition to go in this gap before the gerund.

Hi, Emarbe, The correct preposition is 'with' before readjusting to create a grammatically correct sentence. However, the better option would be to use the infinitive "'to readjust' to changing..." to avoid the awkwardness of the two gerunds. Hope this helps, e.