Hi.. Thanks for the query.. As per your complain it looks like you are getting allergic reaction to the bug bites and it also looks like they are getting infected leading to blister formation.. As it is recurring, there is a possibility that you might have bed bugs and also fleas can also be a cause.. I would suggest you to consult an Immunologist and get evaluated and a thorough clinical evaluation and investigations like blood tests to rule out allergy can help in diagnosis and treatment can be done accordingly.. In case of bed bugs a proper washing and disinfection of your bed sheets, clothes and seat covers of your cars has to be done.. You should also send your cat to pet care centre and avoid coming in contact with your cat where she can be completely get rid of the fleas.. You should apply a combination of steroid and antibiotic ointment over the bite areas.. Maintain a proper hygiene.. Hope this helps.. Regards.